Zombie thread. This inspired me to tinker with my old busted wingman.
The little nubby driver is 1/4" flat made from the package opener. Here's the stack of washers on the top tools.
From left to right: factory plastic spacer | can opener | 3/16"" lock washer | stubby 1/4 driver | factory steel washer.
The lock washer maintains some lateral tension between the tools since you can't tighten the screw without affecting the knife deployment. It has everything on it I need for taking down old rifles and pistols.