100a, fully automatic starter/charger, 20a boost, variable 6 to 2a charge, heavy duty, great for engine starting, & charging, powerful enough for starting suvs, trucks & large batteries, led indicators & button controls, for ease & accuracy, micro processor controlled, automatically adjusts the amperage rate to charge & maintain, multi stage charging for added precision, safety & battery life, reverse hook up protection, charger will not operate if clamps are reversed, 6' power cord, 1 year warranty, 50 state doe compliant.