it is useless. The "lock" mechanism doesn't work and immediately falls apart at the SMALL moment of pressing. You can't use it. Suction power is ok. but you can't use it. general. When I used it, my return policy had expired. The lock is a plastic groove of half a mm. You undo it twice and the half mm edges are now round and do absolutely nothing. I'm so mad I wasted my money on this crap.