Although it was hit by one touch, it was a little high, but I purchased it thought that exchange would be easy if it could be attached to the tip of the drill. But it is not useful at all. It should be one touch but once bit fastened, when applying tension, I got stuck in the inside and could not come off at all. I attached it a few times, removed, put oil, but eventually I think that the phenomenon occurs because the internal strength is losing to the bit tension. I think what happened to holders that would be pinched by the vice every time to remove them. I would like to consider a little more when commercializing it. It is a few days to go to the trash can. It was a very disappointing item.