It can be used to treat all manner of muscular, joint & nerve pain including Arthritis, Period pain, Raynauds disease, Labour pain, Bells palsy & Repetitive strain injury (RSI) Features Of The Perfect TENS60 intensity steps Automatic keypad lock Treatment timer 8 preset programs Dual channel Open circuit detection Detachable belt clip Easy start program memory Safety feature What's Included with the Perfect TENS unit: Perfect TENS Pain Relief unit 2 x Lead wires Pack of 4 50x 50mm Self-adhesive Electrode Pads (E-CM5050)2 x AA 1.5V Alkaline Batteries Instruction booklet Belt clip Storage pouch The electrode pads needs to be applied directly to the skin before the intensity increase buttons will operate. If the perfect TENS detects that the unit is not properly connected to you then the unit will automatically switch the intensity to zero. This stops any unpleasant changes in output. Always read the instructions before use.