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Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
Smartmak® 4 People Indoor Infrared Sauna - Refresh 4

Smartmak® 4 People Indoor Infrared Sauna - Refresh 4
by Smartmak
$5,900.00 - $5,900.00
$5,900.00
$5,900.00 - $5,900.00
$5,900.00

Indoor 4-Person Full-Spectrum Infrared Sauna – 120℉ in 15 Minutes with Red Light, WiFi Control & U-Shaped Bench

Designed for up to four people, this indoor infrared sauna heats up to 120℉ in just 15 minutes using full-spectrum infrared light waves for deep, therapeutic warmth. It also features red light therapy lamps at 660nm and 850nm, supporting skin health, muscle recovery, and cellular repair.

The sauna includes WiFi control, allowing you to preheat and adjust settings remotely via your smartphone. Inside, an oxygen ion generator purifies the air for a fresher environment, while a manually operated skylight vent on the top provides natural airflow and customizable ventilation.

For relaxation and entertainment, the sauna is equipped with a stereo Bluetooth speaker system for high-quality wireless audio and 7-color mood lighting to create the perfect ambiance.

A U-shaped bench offers generous seating and allows users to recline comfortably in a semi-recumbent position, making it easy to stretch out and fully relax during each session.

Ideal for home wellness, this 4-person infrared sauna combines fast heating, full-spectrum infrared, red light therapy, smart controls, air purification, premium audio, and ergonomic seating — delivering a complete spa-like experience indoors.

PRODUCT DISPLAY

PRODUCT PARAMETERS

SIZE

EXTERNAL DIMENSIONS

INTERNAL DIMENSIONS

Width:

71"

Width:

67"

Depth:

47"

Depth:

43"

Height:

75"

Height:

71"

ELECTRICITY DEMAND
Power:
2700 W 
Voltage:

220 / 240 V
Ampere：
15 A

Type of Plug:

NEMA 6-20p

Configuration
Heater:

Full Spectrum + Carbon 
Temperature:

0 - 140 ℉
Mobile-app enabled control system × 1
7-color physiotherapy lamp × 1
Remote control × 1
Breathable skylight × 1
Oxygen bar × 1
Temperature sensor × 1
Reading light × 1
Speaker × 1

PRODUCT DISPLAY

PRODUCT PARAMETERS

SIZE
EXTERNAL DIMENSIONS
INTERNAL DIMENSIONS
Width:
71"
Width:
67"
Depth:
47"
Depth:
43"
Height:
75"
Height:
71"

ELECTRICITY DEMAND
Power:

2700 W
Voltage:
220 / 240 V
Ampere：
15 A
Type of Plug:
NEMA 6-20p

Configuration
Heater:
Full Spectrum + Carbon
Temperature:

 0 - 140 ℉
Mobile-app enabled control system × 1
7-color physiotherapy lamp × 1
Remote control × 1
Breathable skylight × 1
Oxygen bar × 1
Temperature sensor × 1
Reading light × 1
Speaker × 1

PARAMETERS OF THE SAME SERIES PRODUCTS
Model:

Refresh 1

Refresh 2

Refresh 3

Refresh 

4

Refresh 4
Capacity:
1 people
2 people
3 people
4 people
Wi-Fi Control:
√
√
√
√
Full Spectrum Heater:
√
√
√
√
Red Light Therapy:
√
√
√
√
Bluetooth Speaker:
√
√
√
√
Oxygen Bar:
√
√
√
√
7-color physiotherapy Lamp:
7-color Lamp:
√
√
√
√
Temp:
0 - 140 ℉
0 - 140 ℉
0 - 140 ℉
0 - 140 ℉
Voltage:
110V / 120V
110V / 120V
220V / 240V
220V / 240V
Electric Current:
15 A
15 A
10 A
15 A
Exter Dimensions:
Exter Size:
35"W x 35"D x 75"H
47"W x 41"D x 75"H
59"W x 47"D x 75"H
70"W x 47"D x 75"H
Interior Dimensions:
Interior Size:
31"W x 31"D x 71"H
43"W x 31"D x 71"H
55"W x 43"D x 71"H
67"W x 43"D x 71"H

PRODUCT DETAILS

Removable Bench

The width and height of the bench are 45cm / 17.71in, allowing you to sit comfortably inside the sauna and enjoy the sauna.

The bench is removable. This way you can do yoga while enjoying the sauna.

7-color physiotherapy lamp

7 different colors of light can be switched according to your own needs, and different colors of light can be used to balance the "energy" that the human body lacks.

Reading light

There are bright lights on the top of the sauna. When turned on, the entire sauna can be illuminated and you can read under the light without damaging your vision.

Oxygen bar

The oxygen ion converter can convert oxygen in the air into negative oxygen ions to replenish the human body with oxygen and electricity.

Breathable skylight

The breathable skylight on the top of the sauna can exchange gas with fresh air from the outside to maintain the freshness of the air inside the sauna.

Bluetooth Speaker

There are two speakers on each side to create three-dimensional audio and video. You can listen to music and relax while enjoying the sauna.

HEMLOCK

Hemlock Saunas

Hemlock, a type of wood known for its straight grain and uniform texture, is a popular choice for sauna construction. The light color and natural elegance of hemlock wood can add a touch of sophistication to any sauna room. In addition to its aesthetic appeal, hemlock is also highly durable and resistant to warping, making it an excellent choice for sauna enthusiasts seeking longevity and low maintenance.


One of the key advantages of hemlock saunas is their ability to retain heat efficiently. The dense nature of hemlock wood allows it to hold heat effectively, creating a consistent and comfortable sauna experience. Furthermore, hemlock is known for its minimal expansion and contraction in response to changes in temperature and humidity, making it a reliable choice for sauna construction.

1. Scentless

A sauna must be odorless and clean to deliver optimal health benefits. The type of wood used in the sauna affects the odor within it. Strong wood scents, such as those found in cedar saunas, can be overwhelming for some. This is not an issue in hemlock wood saunas.


Hemlock wood offers a light aroma that does not distract you from your sauna session. It is known to be:

Non-toxic

Non-allergenic


This ensures a pleasant sauna experience for everyone. 

2. Shrinkage & Warp Resistant

Hemlock is a supple wood with a clean grain and few knots. This makes it a perfect alternative for both interior and exterior sauna paneling. Hemlock wood panels do not warp or twist due to the heat and moisture in a sauna.


The wood also offers superior scratch resistance and is less prone to splinting. Its durability is unaffected by normal wear and tear. Hemlock wood does not shrink, preserving its form for years. It is an excellent choice for dry heat and infrared saunas due to its heat-resistant properties.

3. Sturdy
Above all, hemlock wood has a robust finish. Despite being a soft wood, its dense structure can withstand extreme heat and moisture. Heat is evenly dispensed within the sauna, ensuring a relaxing experience. Hemlock wood saunas have a long lifespan and require little maintenance.
4. Aesthetic

Aside from its practical purposes, hemlock sauna wood imparts an aesthetic finish to any structure. Sauna enthusiasts prefer the environment of a bright, natural sauna, which Canadian hemlock delivers.


Its light wood grain gives off an earthy vibe. It brightens the sauna and gives it an organic feel few other sauna materials can provide. No wonder it is considered one of the most attractive sauna materials.


The easiest way to identify a hemlock sauna is by its hue, which ranges from light beige to soft brown. If you value aesthetics in a sauna, hemlock should be your material of choice.

5. Inexpensive
Because hemlock is a strong material, it has a higher crushing strength. The heavyweight finish makes it easier to construct a long-lasting sauna. It does not require any fortifying materials to make it sturdier. This makes it more affordable compared to red cedar.

INFRARED HEATER

Carbon crystal heating plate

1. Health risks associated with high heat are much lower in an infrared sauna that uses carbon heaters. The longer wavelengths and lower temperatures get the room up to temperature faster and more efficiently. Carbon distributes heat evenly on its long wavelengths. This process of warming penetrates the skin deeper than the forced heat in traditional ceramic. This results in higher detoxification and a cleaner sweat.


2. Carbon infrared sauna heaters reduce the risk of heat-associated health problems even further. Lower temperatures due to longer infrared wavelengths from carbon heating elements allow your body to safely tolerate longer sessions inside your infrared sauna. Also, infrared heat from carbon heaters penetrates deeper into your skin than infrared heat from a ceramic heater, allowing for more effective therapy and better results.

Full spectrum heater

Full spectrum heater are unique in that they emit near, mid, and far infrared heat all at once. This means that in addition to the far infrared benefits listed above, full spectrum saunas can be good for localized pain relief, cell health, skin renewal, and wound healing.


Adding near infrared heat to the mix is this sauna’s super power. Every cell in our body contains a structure called the mitochondria (a.k.a., “the powerhouse of the cell”). All of our bodily functions rely on them working at full capacity. Lazy or fatigued mitochondria result in dysfunctional systems that many experts argue contribute to conditions like heart disease, Alzheimer’s disease, autoimmune disorders, arthritis, thyroid and/or adrenal imbalances, and even lingering athletic injuries.


However, surrounding the mitochondria are tiny photoreceptors. When exposed to near infrared heat, these receptors cue the mitochondria to pump more oxygen into your bloodstream. These re-energized mitochondria, then, help reverse the damage in the system and, thus, ease the severity of symptoms.

BENEFITS OF USING A SAUNA

1. Relieve stress

Not surprisingly, sauna bathers most frequently cite stress reduction as the number one benefit of sauna use. Medical studies often determine that stress in our daily lives can negatively affect our health. In fact, the vast majority of disease (i.e. heart disease) is at least partially stress-related. Heat bathing in a sauna provides stress relief in a number of ways. It’s a warm, quiet space without any distractions coming from the outside. The heat from the sauna relaxes the body’s muscles, improves circulation and stimulates the release of endorphins. Endorphins are the body’s all-natural “feel good” chemical, and their release provides a truly wonderful “after sauna glow.”.

2. Relax muscles and soothe aches/pains in both muscles and joints

Under the high heat provided by a sauna, the body releases endorphins. Endorphins can have a mild, enjoyable “tranquilizing effect” and the ability to minimize the pain of arthritis and muscle soreness other from, say, an intense physical workout. Body temperature also rises from the heat of the sauna.. This causes blood vessels to dilate, therefore increasing blood circulation. This increased blood flow in turn speeds up the body’s natural healing process via soothing aches and pains and/or speeding up of the healing of minor bruises or cuts. After participating in physical sports, use the heat and/or steam of a sauna to promote muscle relaxation by helping to reduce muscle tension and eliminate lactic acid and/or other toxins that may be present.

3. Flush toxins

Many – if not most – of us do not actively sweat on a daily basis. Deep sweating, however, has multiple proven health benefits. Benefits derived from a deep sweat can be achieved via regular sauna bathing.Due to the heat of a sauna, the core body temperature begins to rise. The blood vessels then dilate, causing increased blood flow. As heat from the blood begins to move toward the skin’s surface, the body’s nervous system then sends signals to the millions of sweat glands that cover the human body. As the sweat glands become stimulated, they produce sweat. Sweat production is primarily designed to cool the body, and is composed of 99% water. However, deep sweating in a sauna can help reduce levels of lead, copper, zinc, nickel, mercury and chemical – which are all toxins commonly absorbed just from interacting with our daily environments.There is no shortage of books from Doctors and practitioners, who describe the benefits of detoxifying our bodies regularly. As many doctors will agree, a big reason for the popularity of saunas is that they are one of the best ways to detoxify our bodies.

4. Cleanse the skin

Heat bathing is one of the oldest beauty and/or health strategies in terms of cleansing one’s skin. When the body begins to produce sweat via deep sweating, the skin is then cleansed and dead skin cells are replaced – keeping your skin in good working condition.Sweating rinses bacteria out of the epidermal layer and sweat ducts. Cleansing of the pores has been shown to improve the capillary circulation, while giving the skin a softer-looking quality. Bathing skin in sweat on a fairly regular basis, therefore deters collagen breakdown that can ultimately result in wrinkles and sags. By continually flushing body waste through individual cells, one eventually brings back vitality, tone and a healthy glow to the skin. Sauna usage is certainly not a cure for acne, but it can very often help – due to the deep cleansing it provides from a deep sweat (that is, cleaning the pores from the very inside out – instead of just cleaning the top of the skin).

5. Induce a deeper sleep

Research has shown that a deeper, more relaxed sleep can result from sauna use. In addition to the release of endorphins, body temperatures, which become elevated in the late evening,fall at bedtime. This slow, relaxing decline in endorphins is key in facilitating sleep. Numerous sauna bathers worldwide recall the deep sleep experiences that they feel after bathing the the calming heat of a sauna.

6. Help burn calories

Outlandish claims are often made by some sauna sellers (primarily those who sell infrared saunas) to promote saunas as an end-all weight loss tool. While some individuals may experience high amounts of calorie burn at first – particularly those individuals in poor shape to begin with – over the long term, saunas are simply treated as one of many tools in our arsenal when it comes to burn additional calories.The sweating process itself requires a notable amount of energy. That energy is derived from the conversion of fat and carbohydrates in a bodily process that burns up calories. According to U.S. Army medical research (Ward Dean, M.D.), “A moderately conditioned person can easily sweat off 500 grams in a sauna in a single session, consuming nearly 300 calories in the process.”The body consumes said calories due to the acceleration of heart activity (the cardiovascular section). As heart activity increases and as these processes demand more oxygen, the body begins to convert more calories into usable energy.

PRODUCT FEEDBACK

HEMLOCK

Hemlock Saunas

Hemlock, a type of wood known for its straight grain and uniform texture, is a popular choice for sauna construction. The light color and natural elegance of hemlock wood can add a touch of sophistication to any sauna room. In addition to its aesthetic appeal, hemlock is also highly durable and resistant to warping, making it an excellent choice for sauna enthusiasts seeking longevity and low maintenance.


One of the key advantages of hemlock saunas is their ability to retain heat efficiently. The dense nature of hemlock wood allows it to hold heat effectively, creating a consistent and comfortable sauna experience. Furthermore, hemlock is known for its minimal expansion and contraction in response to changes in temperature and humidity, making it a reliable choice for sauna construction.

1. Scentless

A sauna must be odorless and clean to deliver optimal health benefits. The type of wood used in the sauna affects the odor within it. Strong wood scents, such as those found in cedar saunas, can be overwhelming for some. This is not an issue in hemlock wood saunas.


Hemlock wood offers a light aroma that does not distract you from your sauna session. It is known to be:

Non-toxic

Non-allergenic


This ensures a pleasant sauna experience for everyone. 

2. Shrinkage & Warp Resistant

Hemlock is a supple wood with a clean grain and few knots. This makes it a perfect alternative for both interior and exterior sauna paneling. Hemlock wood panels do not warp or twist due to the heat and moisture in a sauna.


The wood also offers superior scratch resistance and is less prone to splinting. Its durability is unaffected by normal wear and tear. Hemlock wood does not shrink, preserving its form for years. It is an excellent choice for dry heat and infrared saunas due to its heat-resistant properties.

3. Sturdy

Above all, hemlock wood has a robust finish. Despite being a soft wood, its dense structure can withstand extreme heat and moisture. Heat is evenly dispensed within the sauna, ensuring a relaxing experience. Hemlock wood saunas have a long lifespan and require little maintenance.

4. Aesthetic

Aside from its practical purposes, hemlock sauna wood imparts an aesthetic finish to any structure. Sauna enthusiasts prefer the environment of a bright, natural sauna, which Canadian hemlock delivers.


Its light wood grain gives off an earthy vibe. It brightens the sauna and gives it an organic feel few other sauna materials can provide. No wonder it is considered one of the most attractive sauna materials.


The easiest way to identify a hemlock sauna is by its hue, which ranges from light beige to soft brown. If you value aesthetics in a sauna, hemlock should be your material of choice.

5. Inexpensive

Because hemlock is a strong material, it has a higher crushing strength. The heavyweight finish makes it easier to construct a long-lasting sauna. It does not require any fortifying materials to make it sturdier. This makes it more affordable compared to red cedar.

PRODUCT DETAILS

Removable Bench

The width and height of the bench are 45cm / 17.71in, allowing you to sit comfortably inside the sauna and enjoy the sauna.

The bench is removable. This way you can do yoga while enjoying the sauna.

7-color physiotherapy lamp

7 different colors of light can be switched according to your own needs, and different colors of light can be used to balance the "energy" that the human body lacks.

Reading light

There are bright lights on the top of the sauna. When turned on, the entire sauna can be illuminated and you can read under the light without damaging your vision.

Oxygen bar

The oxygen ion converter can convert oxygen in the air into negative oxygen ions to replenish the human body with oxygen and electricity.

Breathable skylight

The breathable skylight on the top of the sauna can exchange gas with fresh air from the outside to maintain the freshness of the air inside the sauna.

Bluetooth Speaker

There are two speakers on each side to create three-dimensional audio and video. You can listen to music and relax while enjoying the sauna.

INFRARED HEATER

Carbon crystal heating plate

1. Health risks associated with high heat are much lower in an infrared sauna that uses carbon heaters. The longer wavelengths and lower temperatures get the room up to temperature faster and more efficiently. Carbon distributes heat evenly on its long wavelengths. This process of warming penetrates the skin deeper than the forced heat in traditional ceramic. This results in higher detoxification and a cleaner sweat.


2. Carbon infrared sauna heaters reduce the risk of heat-associated health problems even further. Lower temperatures due to longer infrared wavelengths from carbon heating elements allow your body to safely tolerate longer sessions inside your infrared sauna. Also, infrared heat from carbon heaters penetrates deeper into your skin than infrared heat from a ceramic heater, allowing for more effective therapy and better results.

Full spectrum heater

Full spectrum heater are unique in that they emit near, mid, and far infrared heat all at once. This means that in addition to the far infrared benefits listed above, full spectrum saunas can be good for localized pain relief, cell health, skin renewal, and wound healing.


Adding near infrared heat to the mix is this sauna’s super power. Every cell in our body contains a structure called the mitochondria (a.k.a., “the powerhouse of the cell”). All of our bodily functions rely on them working at full capacity. Lazy or fatigued mitochondria result in dysfunctional systems that many experts argue contribute to conditions like heart disease, Alzheimer’s disease, autoimmune disorders, arthritis, thyroid and/or adrenal imbalances, and even lingering athletic injuries.


However, surrounding the mitochondria are tiny photoreceptors. When exposed to near infrared heat, these receptors cue the mitochondria to pump more oxygen into your bloodstream. These re-energized mitochondria, then, help reverse the damage in the system and, thus, ease the severity of symptoms.

BENEFITS OF USING A SAUNA

1. Relieve stress

Not surprisingly, sauna bathers most frequently cite stress reduction as the number one benefit of sauna use. Medical studies often determine that stress in our daily lives can negatively affect our health. In fact, the vast majority of disease (i.e. heart disease) is at least partially stress-related. Heat bathing in a sauna provides stress relief in a number of ways. It’s a warm, quiet space without any distractions coming from the outside. The heat from the sauna relaxes the body’s muscles, improves circulation and stimulates the release of endorphins. Endorphins are the body’s all-natural “feel good” chemical, and their release provides a truly wonderful “after sauna glow.”.

2. Relax muscles and soothe aches/pains in both muscles and joints

Under the high heat provided by a sauna, the body releases endorphins. Endorphins can have a mild, enjoyable “tranquilizing effect” and the ability to minimize the pain of arthritis and muscle soreness other from, say, an intense physical workout. Body temperature also rises from the heat of the sauna.. This causes blood vessels to dilate, therefore increasing blood circulation. This increased blood flow in turn speeds up the body’s natural healing process via soothing aches and pains and/or speeding up of the healing of minor bruises or cuts. After participating in physical sports, use the heat and/or steam of a sauna to promote muscle relaxation by helping to reduce muscle tension and eliminate lactic acid and/or other toxins that may be present.

3. Flush toxins

Many – if not most – of us do not actively sweat on a daily basis. Deep sweating, however, has multiple proven health benefits. Benefits derived from a deep sweat can be achieved via regular sauna bathing.Due to the heat of a sauna, the core body temperature begins to rise. The blood vessels then dilate, causing increased blood flow. As heat from the blood begins to move toward the skin’s surface, the body’s nervous system then sends signals to the millions of sweat glands that cover the human body. As the sweat glands become stimulated, they produce sweat. Sweat production is primarily designed to cool the body, and is composed of 99% water. However, deep sweating in a sauna can help reduce levels of lead, copper, zinc, nickel, mercury and chemical – which are all toxins commonly absorbed just from interacting with our daily environments.There is no shortage of books from Doctors and practitioners, who describe the benefits of detoxifying our bodies regularly. As many doctors will agree, a big reason for the popularity of saunas is that they are one of the best ways to detoxify our bodies.

4. Cleanse the skin

Heat bathing is one of the oldest beauty and/or health strategies in terms of cleansing one’s skin. When the body begins to produce sweat via deep sweating, the skin is then cleansed and dead skin cells are replaced – keeping your skin in good working condition.Sweating rinses bacteria out of the epidermal layer and sweat ducts. Cleansing of the pores has been shown to improve the capillary circulation, while giving the skin a softer-looking quality. Bathing skin in sweat on a fairly regular basis, therefore deters collagen breakdown that can ultimately result in wrinkles and sags. By continually flushing body waste through individual cells, one eventually brings back vitality, tone and a healthy glow to the skin. Sauna usage is certainly not a cure for acne, but it can very often help – due to the deep cleansing it provides from a deep sweat (that is, cleaning the pores from the very inside out – instead of just cleaning the top of the skin).

5. Induce a deeper sleep

Research has shown that a deeper, more relaxed sleep can result from sauna use. In addition to the release of endorphins, body temperatures, which become elevated in the late evening,fall at bedtime. This slow, relaxing decline in endorphins is key in facilitating sleep. Numerous sauna bathers worldwide recall the deep sleep experiences that they feel after bathing the the calming heat of a sauna.

6. Help burn calories

Outlandish claims are often made by some sauna sellers (primarily those who sell infrared saunas) to promote saunas as an end-all weight loss tool. While some individuals may experience high amounts of calorie burn at first – particularly those individuals in poor shape to begin with – over the long term, saunas are simply treated as one of many tools in our arsenal when it comes to burn additional calories.The sweating process itself requires a notable amount of energy. That energy is derived from the conversion of fat and carbohydrates in a bodily process that burns up calories. According to U.S. Army medical research (Ward Dean, M.D.), “A moderately conditioned person can easily sweat off 500 grams in a sauna in a single session, consuming nearly 300 calories in the process.”The body consumes said calories due to the acceleration of heart activity (the cardiovascular section). As heart activity increases and as these processes demand more oxygen, the body begins to convert more calories into usable energy.

FEEDBACK FROM CUSTOMER/INSTALLATION TEAM