Micro current Cordless EMS Mini Massager (1 - 2pc unit & USB cord). EMS (Electrical Muscle Stimulation) Low-frequency pulse massager automatically changes direction every min can help with neck, back,foot, shoulder, leg pain and tight muscles. 8 Modes & 19 Levels Intensity. USB Charging: It Can Be Used Continuously for up to 8 Hours After Charging for 0.5 Hours. Dimensions approx. 5.9 x 2.75 x 0.9 inches