Custom designed HARDENED stainless steel spanner. Its ingenious head design fits Chapman, Fisher, and most other Mitchell nuts.
Machined from 1/4" hardened 410 stainless steel. It'll stand up to the kind of abuse we like to dish out on set. The handle has a nice dog leg offset to prevent knuckle busting, and although we'd never recommend it... the handle design allows a short piece of speed-rail to be used as a "cheater" in those difficult situations. Its pleasing design makes it feel good in your hand. A great gift for your favorite dolly grip. 

NOTE: previous versions were not hardened.