Simple and powerful soothing relief for muscle pain and stiffness - using the tens (transcutaneous electrical nerve stimulation) method to block the pain message and help enhance circulation, find soothing relief for muscle aches and pain precisely where you need it, whether for your neck, lower back or legs and all the points in between. Small control unit is in your hand - the compact size of the control unit is ergonomically designed to allows it to sit comfortably into one hand for an easy and effortless one hand operation. 2 Long life pads - soft and comfortable, these self-adhesive pads are durable and long lasting as they are able to be used for up to 150 times with 10 washes.