Why do I call them "Blocker" rings? Because they block gear clash. These little items will act as a clutch, brake, and directional assistant. When you fist push that shifter handle the synchro ring shoves the shift dogs into the blocker ring slots. They in turn shove the blocker ring closer to the gear. This clutch action causes the gear to slow down or speed up. Once it is in Synchronized Rotation with the collar the little brass pyramids direct the collar onto the gear teeth for complete engagement
