The moisture meter can quickly measure the moisture content of the grain. 1. The built-in red light that reaches the inside of the knee can cleanse impurities from body fluids and blood, speed up blood circulation and remove joint effusions. 2. Three-stage temperature, heat energy penetrates the skin, accelerates blood circulation, cleanses meridians and protects the knees from moisture and cold. 3. Built-in high frequency vibration motor, versatile knee muscle vibration massage, completely release pressure. 4. Built-in infrared laser sensory lamp, 615-650NM wavelength, 4-16 nanometer wavelength, irradiate the knee joint directly into the deep knee layer. 5. LED display, highly visible, real-time massage status control, one-button start and simple operation. Specification: Item Type: Knee Massager Material: ABS Built-in battery: 3000 mAh lithium battery Temperature: 3 gear temperature (40 /42 /45 ) Operating temperature: 5-40 Relative humidity: 80% How to use: 1. Please fully charge the product before first use. Charging time is about 2-3 hours. 2. Then press the switch button to adjust the temperature, vibration and phototherapy effect according to your individual needs. List of packages: 1 x Knee Massager 1 USB cable 1 x Manual