uses a new bit to drill a pilot hole in a piece of teak before screwing another piece. Partially cut the second pilot hole and drill bit and then rotated freely in the base, when I tried to rotate the drill bit out of the hole the base came loose from the drill bit and we had to remove the drill bit from the wood with a small channel lock pliers. These things are nothing more than garbage. I would not recommend anyone to buy them, friend or foe.