Utilizing Low Permeation Tank Technology, Moeller fuel tanks are EPA low perm certified and conform to all ABYC, NMMA, and USCG regulations. The below-deck tanks utilize durable marine-grade, rotationally molded, cross-linked polyethylene plastic thats corrosion and pit resistant. Fill spouts, withdrawal, and vent fittings are molded directly into the shell. Machined aluminum 3/8 withdrawal fitting has 360° rotational capability for hook-up convenience. Tank capacity: 15 gallons. Dimensions: 18.5W x 17.75L x 12.5D.Please note: Hydrocarbon swell causes tanks to expand by 3% in all directions. When measuring, please allow for this expansion as well as an extra 2-1/2 for fittings. Actual fill capacity can vary by +/- 5% of the printed capacity due to how the tank is installed in the boat and variances in the outside temperatures.