【621501-10 Manual Vent Gas Cap】 The marine gas tank cap is specifically designed to be compatible with old style portable M'oeller and T'empo fuel tanks. 【Manually Vented】Our vented gas cap for boat fuel tank features a twist valve for adjustable ventilation. Fits tight with no leaks and the vent screw is easy to turn for release and close. 【Wide Compatibility】The marine fuel tank cap is compatible with a wide range of fuel tank models, including 031103, 031106, 031109, 031112, 031212, 620003, 620049, 630012, 630013, 630014, 620040, 720040, 730014, and 730025 portable boat gas tank. 【Compatibility】Boat gas tank cap fits A'ttwood 12 gallon, 6 gallon and 3 gallon tanks, B'ass Tracker boat tank, S'cepter 12 gal and 6 gallon tank, 3 gallon Q'uicksilver plastic gas tank, old 6 gallon plastic Dura-Tank Essence, M'ercury plastic tank, Y’amaha and more. 【High Quality Material】The vented gas cap for boat fuel tank is made of high hardness plastic materials, which is well made, sturdy, will not rust, resistant to corrosion and aging, well tested to ensure long service time. 【Easy to Use】No tools needed, simply by turning the top of the tank gas cap and allow your tank to vent properly.