Permanent below deck fuel tanks with molded-in hold down grooves for secure mounting. Moeller 90 degree fill series permanent tanks are favored by quality boat builders. They are made of cross-linked rotationally molded polyethylene that is impervious to corrosion and ethanol-enhanced fuel. Tanks meet all ABYC, NMMA and U.S. Coast Guard regulations. They come equipped with an electrical fuel sending unit for use with a dash-mounted gauge. When selecting a tank, bear in mind that tank dimensions do not include fittings, so for the true height of the tank, add 2 1/2" for the fill neck and add 3% to measurements to compensate for hydrocarbon swelling in all directions. All tanks include a machined aluminum 3/8" withdrawal fitting that swivels 360 degree for ease of installation. Tanks are for gasoline or diesel. For diesel installations, order Sending Unit with Return Port, Model 8843559). These tanks are not UV protected and are for below-deck installation only. The innovative low-profile, 360-degree adjustable fuel pickup tube ensures optimal hose alignment between the engine and fuel tank, significantly minimizing the risk of fuel hose kinking.