ANDIS MASTER CORDLESS LITHIUM-ION CLIPPERBuilt around a high speed rotary motor that runs at 7,200 strokes per minute and can cut wet or dry for effortless bulk hair removal. It features Constant Speed Technology so it won't stall or drag. The motor's housed in an unbreakable and ruggedly good looking aluminium casing that's shaped to be comfortable to hold. Power comes from a lithium ion battery that'll run for 90 minutes and reaches full charge in just 60.