This single channel 2 pad low volt muscle stimulator is quite a unit for the money. It is a workhorse and yet affordable. It features adjustable pulsation and surge rates, surge mode ramped, tetanize mode, intensity reset circuit, 30 minute timer, combination therapy capabilities, It is UL listed and comes with a 2 year warranty - parts and labor. It weighs 3 lbs. and it's dimensions are 7 3/16" wide x 7 5/16" deep x 4 11/16" high.