Turn shafts snap into the accessory opening on the side of Yun Sheng (NOT Sankyo) full size 18-note musical movements. Note that it does *not* extend the winding key shaft. Instead, it goes in a completely different hole on the musical movement box. Turn shafts are used to drive things like crank style assemblies, orbital motion rods and some small metal turntables. It cannot be removed once it has been snapped in place.
Extends approximately 1/4" (6mm) from movement when installed.