An extra heavy "O" ring to assure watertight fit. To be installed in areas where internal pressure (oil-canning) is NOT present. Ideal for inspection compartments, for clean out or access to shut off valves, back-up fasteners.
                                    - Hole: 6-1/2"
 - Color: White
 - ID: 6-3/16"
 - Center: Diamond
 - OD: 8-1/8"
 

