Semiconductor Thermoelectric Cooling Utilizes advanced semiconductor technology for rapid cooling and heating through the wrist, enabling efficient physical temperature control. Versatile Temperature Modes Features three adjustable modes for both cooling and heating, allowing customization from gentle to intense for various needs. Instant Cooling Relief One-touch activation provides immediate cooling sensation that spreads throughout the body, perfect for hot environments. Comfortable Silicone Strap Employs mature liquid silicone technology for a soft, smooth, and elastic feel, comparable to baby skin texture. Quiet Operation Engineered for low noise levels, ensuring a comfortable and undisturbed user experience. Specifications:Operating Modes: Cooling and HeatingBattery Capacity: 500mAhOperating Temperature Range: 5 - 45Charging Interface: Type-CNet Weight: 48gBattery Life: 1.5 hours (Cooling), 2.5 hours (Heating)Material: Silicone