The Tosi™ Collection is the only true full spectrum sauna on the market, making it one of a kind. While many brands claim to offer a full spectrum sauna, in reality they do not meet the full criteria. Tosi™ heaters are revolutionary because they are equipped with mid and far infrared combination heaters while advanced LEDs provide near infrared. Together they produce the full spectrum of infrared. Having access to the entire spectrum means you get the maximum benefit of all wavelengths. Hello Tosi™, Goodbye Toxins.