I have had a few 5C collet chucks through the years, and the latest one by Bison takes 2-3X as many crank turns on the chuck key to get the collets seated. With some arthritis in my hands, it wasn't much fun twirling the chuck key a zillion times to change collets. Ideally, maybe a 5C speed chuck or collet closer would have been better but more pricey. I had a spare vise speed handle that I wasn't using, so decided to modified for use on the 5C chuck. Using the center hole, a 3/4" rod fits perfectly in the hex. I used some 3/4" oil rod, machined flats for the key end and and then secured it to the speed handle handle with a 5/16" fine thread pointed set screw. Very rigid, and makes much quicker work of switching collets. The added benefit is that there is enough leverage using it like a T handle to lock the collet in securely and it is very comfortable to use. My hands are happier.