Three Ball Handle
SC4 Three ball crank handle
This handle mounts on a 10 mm shaft and has a shallow 3 mm keyway.
The crank handle is 75 mm from outside of ball to outside of ball. The handle is 53 mm overall length.
Part 205A on the SC4 bench lathes 3536 and 3540 (SC4-205A).
In your instruction manual, this part appears on the parts list as: