When a bolt is fastened in a round hole, a crescent-shaped gap is formed. The locking washer was developed in a series of innovations for providing a support hook in the crescent-shaped gap to prevent the bolt from moving.

A support hook fixes the bolt in place when tightening it with a nut or when loosening the nut from a rusty bolt. The support hook also keeps the nut locked in place when fastened.

The support hook is formed on the locking washer, fitting in the crescent-shaped gap. The locking washer holds onto the bolt head, preventing it from turning as the nut is tightened.

The locking washer can also be used in combination with a nut to prevent it from loosening.

The locking washer has been patented in eight countries, including Japan.

Ohshin is currently seeking business partners to further develop their locking washer.