A wildly efficient machine you'll love. At 10,000 rpm, there's no stopping it! No lint is left behind. Remove all pilling / lint on clothes, furniture, carpets, EVERYTHING. Lithium-ion battery can be charged with USB up to 1000 times. Lasts for 1000 charges. Holds power 7-10 times longer than other batteries. A wildly efficient machine you'll love. You will be SO surprised.