Clamp-style two piece shaft collars are designed to solve the problems associated with the set-screw collar.  Instead of protruding into the shaft, the screws act to compress the collar and lock it into place. The connection between the shaft and the collar is made with friction. The ease of use is maintained with this design and there is no shaft damage. Since the screws compress the collar, a uniform distribution of force is imposed on the shaft, leading to a holding power that is nearly twice that of set-screw collars.