I was talking to a friend at out last meeting about vacuum chucks. He has the same one as me but his holds better. He told me he took the two O-rings off and put a new end on it. He bought it at www.rubberchucky.com. I went there and bought one for mine and was amazed at all of the products they have. They have the drive and end for three sided bowls, sphere cups, drive and center for pepper mills and many other things. If anybody is looking for anything different check them out. I am not affiliated with them in any way. I was just impressed with the selection of products they have.