iStim EV-820: Digital TENS stimulator comes with 2 channels, 5 TENS modes and 12 preset programs, sending comfortable impulses through the skin that stimulate the nerve fibers in the treatment area. Safe and highly effective stimulation helps for treating chronic or acute pain (e.g. shoulder tension, back pain, arthritic, knee pain) and providing muscle relaxation and muscle strengthening. JAPANESE ELECTRODE PADS: High-grade, and biocompatible 100% SEKISUI Japanese gel, which is the harmless ingredients and the best fit for even sensitive skin users. APPROVAL: Safe, all-natural, drug free and long-lasting pain relief. 510K approved for OTC use and safety regulations (IEC60601-1, IEC60601-1-2 EMC) certified. Made in Taiwan. INCLUDING: iStim EV-820 Tens Unit x 1; Electrode Pads x 8; Lead Wires x 2; Instruction Manual x 1; Quick Guide x 1; 9V Battery x 1; Sealable Bag (For electrode) x 1 NOTE: DO NOT USE EXTRA ELECTRODE GEL