Polishing pigtails allow you to transfer the power from a bench grinder or drill to take a polishing or finishing mops. The tapered nose is easily attached to the power source, then the buffing wheel screws onto the tapered nose. It tightens up once the motor is switched on. It's important that you select the correct fitting side, as you want the pigtail to tighten when in use and not loosen.
Having it attached to a bench grinder allows you to have both hands free for working on the item. It also means that you don't have to keep changing tools as a mop or abrasive wheel can be easily changed out. The thread of the pigtail has great gripping capabilities once fully tightened up.