About this item Package Included 1 x Black Fuel Tank Cap,1 x Silver Flange Cap,1 x Seal O-Ring Features Overflow coolant tank caps are designed to fit OEM coolant tanks with a threaded fill neck Complete replacement caps are machined from billet aluminum, with a polished surface comes with pressure cap. Application The weld on filler neck and cap is suitable for oil tanks, fuel tanks, water tanks, dry fuel tanks. Complete replacement caps are machined from Cap Material 6061-T6 Aluminum alloy, with a polished surface comes with pressure cap.Scalloped design, making them the perfect complement to any engine bay.A clear anodized finish adds shine and durability Cap OD Size 1.5″ /38mm, 2″/50mm, 2.5″/63mm,3″/76.2mm,4″/101.6mm.(Please buy according to your needs and the size in the picture).