This is a very simple machine with only one channel and 8 different mode patterns. It also has 10 different intensity levels and 10 different speed levels with an LED display. It uses 2 AAA batteries . Very easy to use. It uses a 2.5 jack input for the lead wire, and can be purchased with either Pin or Snap leads. The Pin kit will come with 1 set of 2.5 4 pin leads and 1 sheet of 4, 50 mm square pads. The Snap kit will come with 1 set of 2.5 4 snap leads and 1 sheet of our 42 x 64 oval snap pads.