Finnmark FD-5 Trinity XL 3-IN-ONE / Spectrum Plus infrared heaters, Traditional Steam Sauna Heater & Spectrum Red Light™ Therapy Combo (4 Person)Finnmark FD 5 Trinity XL 3 IN ONE The Trinity Combination Sauna is the only sauna available that combines Finnmarks UL listed Spectrum Plus infrared heaters combined with a traditional sauna heater that uses vulcanite sauna stones to radiate and even heat and allow you to splash a ladle of water onto the rocks for steam. True medical grade Spectrum Red Light Therapy rounds out this multi dimensional home wellness system. Dont compromise! Finnmarks FD