PLEASE MEASURE THE DIAMETER OF YOUR FUEL TANK FILL TUBE PRIOR TO ORDERING! One keyed alike pair, 3” diameter, 8 UNNS locking aluminum diesel fuel cap. Fits select Volvo & Mack ultra low sulfur labeled or PNG tanks 2010 & later. Cap is not vented, fuel tank must be vented, for low sulfur diesel applications only. Supplied with 4 matching keys (keys are not available separately) Includes rubber gasket seal, safety chain, and bail. Approximate dimensions = Across threads cap 3” Approximate net weight = 1 lb 5 oz/pair Replaces: Fuel Tank Accessories️#FTA-C-722L