Used-condition distributor drive spindle/gear for A-series engines only. These frequently get damaged or lost when engines are taken apart, so we usually have some on hand, just in case. The spindle must match the drive engagement at the bottom of the distributor to be fitted to your engine. Note the narrow drive slot in this spindle, which fits pre-A+ distributors only. Sold each; actual condition may vary from photo. Ref: 12G4499, U-12G4499, 12G4499-USED.
See 12G3560 for A+ drive spindle with wider drive slot.