Brand new Kelch threaded marine style 6″ long vented gas cap. This brand new Kelch gas cap is a 2 1/4″ diameter threaded gas cap. Kelch is no longer producing these gas caps, once we sell out they are gone forever. The gas cap has the adjustable screw vent in the center of the gauge face. It is very important to measure your tank depth! Measure from the top of the filler neck threads, straight down to the tank bottom. Make sure your tank is at least 6 1/2″ deep for this gas cap. These gas caps do not fit the new EPA Moeller tanks, only the old style. These gas caps are know to work on Moeller, Chilton, Yamaha, Attwood, and Honda plastic tanks. If your tank is a different depth, just contact us as we have several lengths available. We have these gas caps available in lengths of 6″, 6 1/2″, 7 1/2″, 8″, 9 1/4″, 10 1/2″, 11 1/2″, 12″, 13 1/2″, 15″, and 16″ Any questions, email us or call the shop at 517 787 0477.