An O-ring is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a disc-shaped cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface..
Sheet Metal Screw, #10 x 1/2 in, Zinc Plated Steel Hex Head Hex Drive, 30 PK Sheet metal screws make excellent fasteners for attaching metal hardware to wood because the fully threaded shank provides good retention in wood..
.3/8"-16 x 1-1/4" Zinc Plated Grade 5 Steel Coarse Thread Carriage Bolts 10PK The square section grips into the part being fixed (typically wood), preventing the bolt from turning when the nut is tightened.