MC Pushrod
The pushrod is held in the master cylinder with a rubber retainer. The retainer looks like a short piece of vacuum hose with a groove in the side. DO NOT install the pushrod without one. I've had to chuck the pushrod up in a vise and whack the master with a BFH to get them out. The pushrod and retainer install very easily into the new master. You can usually feel the pushrod seat when you get some resistance built up while bleeding.