Description 9 Inch (Large) Allen Hatch – Includes hatch cover and base but no “O” ring. The gasket (body) is fixed to the hull of the boat and the A.638 O ring is placed around the gasket, under the small lip. The hatch cover lid is then screwed tight onto the gasket and forms a seal with the O ring around the external diameter of the hatch. Cut Out Size: 241mm Fixing Hole Diameter: 3mm Opening Size: 223mm O Ring Required: A.638 Weight: 266g
