The Corbin Russwin 650F54 is used on the ED4400, ED4800, ED5400 and ED5800 Surface Vertical Rod Devices as the Top Latch Strike. The Strike used to have a roller on it, they no longer have the roller.
Standard duty brass 2-1/4" knob is pinned to swivel spindle for 1-3/4" door. Outside spindle is 3/8" solid center and inside spindle is 9/32". Inside knob threaded 3/8-20 with two case hardened set screws.
This Corbin Russwin Adjusting Nut is used on the Corbin Russwin Mortise Lever Locks. It threads into the end of the spindle. 2-3/8" overall length, 9/16" thread length, 1-15/16" bolt length. The threads are 1/4-28.