For buckets with recessed holesUse: Fang bolt, hexagon nut, spring washer and domed washer. For plastic buckets with flat holesUse: Fang bolt, hexagon nut, spring washer and large flat washer. For steel buckets with flat holes Use: Euro Bolt, hexagon nut, spring washer and small flat washer. Euro Bolt Fang Bolt Domed Washer Large Flat Washer Spring Washer