Product * Independent mode control. you can set separate modes and intensities for channel a and channel b. ( For example, you could choose kneading mode in channel a with an intensity level of 5 for your shoulder. while in channel b, the tapping mode is being run with the intensity set to level 12 on your lower back as a back electric stimulator. ) * Up to 6 modes. pre-set modes offer you hammering, kneading, shiatsu and more choices to help relieve pain associated with aching and fatigue muscles in the shoulder, low back, knee from exercise, normal household or work activities. * Continuous use, it can be connected to wall charger, power bank or laptop USB port to charge. don't worries about treatment interruption for dead batteries any more. * Pain relief machine. the rechargeable electric muscle massager can stimulate the sensory nerves and muscles, activate specific natural pain gate mechanism, relax your body and have pain management any time you feel the need. Specification: Material;ABS Size: 167 x 71 x 29mm Modes: 6 Kinds Levels: 15 Levels Display: LED Screen Input: 4.5V-5V Output Power: 4W Output Frequency: 1-330HZ Battery: Built-in Battery Package Includes: 1 x Dual Channel Tens Machine 2 Pair Electrode Pads, 2 x Lead Wires, 1 x Usb Cable 1 x User Manual Note: 1. Due to the light and screen difference, the item's color may be slightly different from the pictures. 2. There is 0-1cm difference according to manual measurement. Thanks for your understanding.Products from GuanGuan's store