900-1800nm natural protection light has stronger penetrating power, internal and external fading, interception and containment, skin protection for 3 minutes every day, source anti-black promotion twice a week, triple check, 2 fast metal sheets will only emit light waves when they are close to the skin, prevent light leakage and glare, continuously detect skin surface temperature by mistake, and automatically cool down to the appropriate skin temperature when reaching 43 constant temperature device.