Perko Chrome Gas Deck Fill with Black Plastic Cap and FlangeDeck fill with black plastic splash guard and cap with strap. Features key less, easy to use cap with tabs. Chrome Plated zinc alloy. Requires grounding per u.s.c.g. requirements. For Hose Size: 1-1/2"; O.D. Flange: 3-1/8"; Length of Neck : 1-7/8"; Mounting Hole Dia.: 2-1/8"; Screw Size: #6;