A gearbox inner to outer cover gasket for Triumph T160 Trident motorcycles. The original part number for this gasket is 57-4878.
For Triumph T160 Trident Painted Fuel Tank + Cap U.S. Specification
TRIUMPH T160 TRIDENT TIMING ROCKER SHAFT BUSH - 70-6018
Triumph T160 Trident 750 Triple Owner's Handbook Electric start Book
48 Piece Gasket Set - Triumph T160 Trident 1975-77
TRIUMPH T160 TRIDENT OIL PUMP SCREW - 2-1/2" - 71-4236
TRIUMPH T160 TRIDENT CLUTCH INSPECTION COVER - 57-4911