Made from marine-grade, cross-linked polyethylene, all tanks are USCG, NMMA and ABYC compliant. Mechanically vented cap floats and is easy to grip, with ribbed design. Tanks include 90°, 1/4" NPT, Moeller-patented “Poplock” aluminum withdrawal elbow that swivels 360° without losing its seal. Rotomolded 2 1/4" fill neck with gauge and vent.