Finnmark FD-4 Trinity 2-Person Infrared & Steam Sauna Combo

The FD-4 Trinity combines three distinct wellness experiences in a single 2-person cabin without compromise. UL-listed Spectrum Plus™ infrared heater panels deliver deep, penetrating heat for a cleaner, more efficient sweat. The Harvia Vega Compact 1900 Finnish steam heater reaches up to 190°F with splashable rocks for an authentic löyly experience. Spectrum Red Light™ medical-grade near-infrared ceiling panels round out the session with cellular recovery and rejuvenation. The naturally antimicrobial Western Red Cedar interior resists mold and odor, while the Thermo-Aspen exterior resists rot, warp, and decay. Double-walled construction ensures efficient heat retention, and the extra-large two-tier bench system comfortably accommodates two bathers. An 8mm tempered glass door, LCD Wi-Fi touchscreen with Bluetooth audio, and 6" Hi-Fi speakers bring modern convenience to every session. Plugs into a standard 120V NEMA 5-15P outlet with no special wiring required.

Three modalities

Infrared: UL-listed Spectrum Plus™ heater panels deliver deep, penetrating heat for a cleaner, more efficient sweat up to 170°F.

Traditional steam: The Harvia Vega Compact 1900 Finnish steam heater reaches up to 190°F. Ladle water onto the splashable rocks for an authentic löyly experience.

Red light therapy: Spectrum Red Light™ medical-grade near-infrared ceiling panels support cellular recovery and rejuvenation to complete every session.

Key features

• 2-person 3-in-1 infrared, steam, and red light therapy sauna
• UL-listed Spectrum Plus™ infrared heater panels for deep, penetrating heat
• Harvia Vega Compact 1900 traditional Finnish steam heater with splashable rocks
• Spectrum Red Light™ therapy, medical-grade near-infrared ceiling panels
• Western Red Cedar interior, naturally antimicrobial, mold and odor resistant
• Thermo-Aspen exterior, rot, warp, and decay resistant
• Reaches 170°F infrared / 190°F steam on a standard 120V outlet, no special wiring required
• LCD Wi-Fi touchscreen control panel with Bluetooth audio
• 6" Hi-Fi speakers and Spectrum LED near-infrared ceiling lighting
• 8mm tempered glass door with gasket
• Extra-large two-tier bench system for 2 persons
• Double-walled construction for efficient heat retention
• Low EMF, tested by a NASA award-winning facility
• ETL listed

Brand: Finnmark Designs
Model: FD-4
SKU: TRINITY-4X4
Origin: Europe
Capacity: 2 persons
Exterior Dimensions: 48"W x 48"D x 83"H
Interior Dimensions: 44.25"W x 45.5"D x 75.5"H
Room Volume: 86 cu. ft.
Door Dimensions: 23.625"W x 68.875"H
Glass Thickness: 8mm tempered with gasket
Interior Material: Western Red Cedar
Exterior Material: Thermo-Aspen
Infrared Heater: UL-listed Spectrum Plus™ panels
Max IR Temperature: 170°F
Steam Heater: Harvia Vega Compact 1900
Max Steam Temperature: 190°F
Red Light: Spectrum Red Light™ medical-grade near-infrared panels
Infrared Power: 1,750W
Voltage: 120V / 15 to 20A / Single Phase
Plug: NEMA 5-15P (standard outlet)
Control: LCD Wi-Fi touchscreen
Audio: Bluetooth and 6" Hi-Fi speakers
Product Weight: 437 lbs
Shipping Weight: 618 lbs
Shipping Dimensions: 80"W x 40"D x 58"H
Certifications: ETL listed, low EMF tested
Warranty: Limited manufacturer warranty

• Complete sauna cabin kit, all panels and hardware
• UL-listed Spectrum Plus™ infrared heater panels
• Harvia Vega Compact 1900 steam heater with controls
• 29 lbs box of Harvia AC3000 sauna stones
• Spectrum LED near-infrared ceiling lights with Spectrum Red Light™ therapy
• Wi-Fi LCD touchscreen control panel with Bluetooth audio
• 6" Hi-Fi speakers
• 8mm tempered glass door with handle
• Extra-large two-tier bench system
• Power supply, cables, and installation hardware
• Installation and operation manual
• ETL Safety Certificate and limited manufacturer warranty

Please note that each natural stone is unique in shape and size. We recommend purchasing an additional box of sauna stones to allow you to choose the highest quality of stone for fit, form, and function (Additional freight charges will apply if purchased separately).

The FD-4 Trinity arrives as a modular kit and assembles with the included hardware and installation manual. Plugs into a standard 120V / 15 to 20A NEMA 5-15P household outlet with no special wiring or dedicated circuit required. Load the included Harvia AC3000 sauna stones into the Harvia Vega Compact 1900 heater basket before first use. Connect via Wi-Fi and pair Bluetooth audio through the LCD touchscreen controller. Refer to the included installation and operation manual for full setup and operating guidance.

• EMF Test Log
• Installation Manual
• Controller Manual
• Finnmark Certification
• Harvia Vega Heater Installation Manual

For general wellness purposes only. No medical claims are made or implied. Results are not guaranteed and may vary. Always consult a qualified healthcare professional before use, especially if you have a medical condition, are pregnant, nursing, taking medication, or use an implanted electronic device.

10-year limited manufacturer warranty. Covers manufacturing defects in materials and workmanship under normal residential use. Does not cover damage from improper installation, misuse, neglect, or unauthorized modifications. Contact support@marterraelements.com with your order number, photos, and a description of the issue. We aim to respond within 2 to 3 business days. Warranty is non-transferable and requires original proof of purchase.

Finnmark Warranty

Free shipping to the contiguous United States. Ships on a wooden pallet by appointment with curbside delivery; customers may be contacted prior to shipment to coordinate delivery and discuss any site-specific requirements. Remote delivery areas may be subject to additional charges.

Returns are accepted within 30 days of delivery and require prior approval before anything is sent back. Please reach out to support@marterraelements.com to get the process started. Items must be unused, undamaged, and in their original condition with original packaging intact. Change of mind returns are subject to a restocking fee of up to 20%, and return shipping costs are the responsibility of the customer. Proof of purchase is required for all returns.