Amarine-made Boat Marine Flush Mount Fuel Gas Tank Vent 90&deg; Stainless Steel for 3/4 Hose High Quality stainless steel 90 degree tank vent fitting includes gasket for installation Mounts flush to hull so there are no protruding caps too get broke or damaged This has wire mesh filter to prevent debris entry into vent line. Cap unscrews with a hex head wrench to clean the filter screen or to pressure test the fuel system. Will work with 3/4" fuel vent lines Maximum hull thickness is 1" Hole size required for installation is 1 1/2"