1、LONG LASTING: Rechargeable lithium ion batteries provide lasting power and can be used multiple times, please charge it before first use. With automatic closing function. 2、ELECTRIC: Drug free and highly effective electronic TENS units and pain relieving for joints, back, knees, give you more pulsing muscle stimulation effects. 3、MULTI FUNCTION: Whether chronic pain or muscle soreness, the smart cervical massage pad can meet your different needs, safe to use without skin damage. 4、WIRELESS DESIGN: It is designed to allow users to move freely and discreetly under clothing, no need wires, no remote control, not easy to be noticed. 5、PORTABLE: The compact design makes it very easy and convenient to carry and use. Suitable for use at home, at work and outdoor. It is the ideal gift for your family.Item Type: Cervical Massage Pad Material: ABS Size: Approx. 44 x 44 x 10.5mm / 1.732 x 1.732 x 0.413in Battery: Lithium battery (shipped with built in battery) Battery capacity: 90mAh Power supply mode: USB cable Use method: Mode strength user adjustment appropriate. 1. Press the host key to start up, at this time the host green light flashes, the host is waiting for instructions, such as 120 seconds of controlled instruction host automatic shutdown. 2. After starting up, press the power plus button and the green light will be steady on (25 gears of power plus). 3. Press the middle switch mode compound key (press for one second to switch mode). There are 11 modes in which the power returns to 0 gear, and the power needs to be adjusted again. Long press for three seconds to shut down) 4, strength reduction key (strength reduction key 25, adjust to 0, the green light flashes)5, DC5V USB charging port, the machine is 3.7V 90MA lithium battery, charging time is 1 hour. The internal lithium battery of this machine starts up and works for 15 minutes each cycle. The lithium battery can work continuously for 3 hours when it is full. Please charge it in time when it is prompted that there is no power. When the product is not in use, please ensure that it is charged at least once within 3 months (full).hout1 x Host 5 x Pad 1 x USB Cable 1 x Storage board