The differential cover is a 1 piece 3/8" (.375") plate steel cap bent 8 ways then welded to a 3/8" ring! The fill plug is a generous 1" ID for easy fill and oil level check. After welding the mounting surface is machined absolutely flat for a perfect fit!
These fit both 10.25" and 10.5" sterling rear ends
Product make by Ruffstuff Specialties. Best diff covers on the market, sold here for your convenience.