US Patent 7467510 Chain link anti-knuckle insert

An insert assembly adapted to be received within a link of a chain including a plurality of round wire interlocking links, the insert being made of a resilient material and being dimensioned to be wider than the central area height and longer than the central area depth so that after the insert is placed between the opposed sides of the chain, the insert springs back around the opposed sides of the chain so that the insert is securely locked between the opposed sides of the chain. The insert has a central opening, and the insert assembly further includes a pin secured in the opening when the insert is received in the chain central area so that the insert cannot move away from the chain opposed sides.