Bonded Sealing Washers (inch)
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Bonded sealing washers feature a silicone rubber flat circle with a galvanized metal backing. These washers are primarily used for vibration absorption or weatherproofing. The bolt or screw will be inserted through the center of the flat washer so that it rests between the head of the bolt and the connecting material. The galvanized backing should be against the head of the bolt with the rubber side against the connecting material. Flat washer sizing is called out by the bolt size so if you are using a ½” diameter bolt, you will need a ½” diameter flat washer as well.