Power supply: USB charging or three AAA batteries
The product itself does not have a battery, you need to buy a battery to use it

Description:

It can relieve stress, pain, muscle tension and increase blood circulation; 

It helps to relieve tension, stiffness, insomnia, and fatigue;

It is helpful to make you relax. 

Features:

Color: Blue, Pink, Red, Orange, Yellow, Green

Material: sponge,ABS

Nature: small and easy to carry; powerful and not hot; good elasticity; flexible

Function: through the acupression to make the body blood flow unimpeded. 

Notes:

Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Please allow 1-3cm measuring deviation due to manual measurement.