High Emissivity infrared heaters High quality double walled construction with non-toxic wool insulation. Interior Heater Connections with Wood Cover Removable and adjustable sauna feet for uneven surfaces Spectrum LED near infrared ceiling lights combined with medical grade Spectrum Red Light therapy. Controller 2.0, built-in LCD touchscreen control panel with Bluetooth audio Audio upgrade with 6" HiFi speakers 8mm tempered glass for the ultimate thermal retention