Manufactured from marine-grade cross-linked polyethylene material, these durable below-deck tanks meet and exceed all industry standards. Moeller permanent fuel tanks are equipped with a Stewart Warner electric sending unit, a 1/4" NPT aluminum withdrawal, and a molded plastic barbed vent. Not for use with diesel fuel. 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. Additional $5.00 shipping charge.