A two-pound dead-blow hammer, often mistaken for a rubber mallet. The primary tool of the hacks at Orange County Choppers, especially Paulie. Chiefly used for axle installation, engine/transmission alignment and primary cover installation.

Properly used, an OCC wrench is a useful tool that one occasionally needs for stubborn, rusty old parts, not shiny new ones that should slide together if one knows what they are doing.
I have been a motorcycle mechanic for ten years, and have never needed the OCC wrench to put in an axle.

Look, that idiot Paulie dinged that primary with the OCC wrench!
by Dr. Badwrench February 23, 2008
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