One combined product eliminates the need to install both a fuelline vent and a surge protector. Inertia of surging fuel drives thesurge ball against upper seat, closing the large vent opening andlimiting passage to smaller openings, which reduces fuel flow andminimizes spillage. Operates in any orientation within 45° of vertical.Baffles resist water intrusion during normal sea conditions and washdown. Constructed ofglass filled polypropylene to withstand oil, gas, alcohol blended fuels. Meets ABYC standards. Fits5/8" ID hose. Max. 1/4" hull thickness. Two spacers included to allow hull thickness up to 1". Requires1-3/8" installation hole.