Exhausted from work but by darn it I was in in time to catch some Wednesday CW drops. So dropdeck on stand by we move to the attack. Not my best but good and fun all the same. Hope you enjoy.
A fastener such as a Nut and bolt, Or washer has a series of spikes or teeth on a bearing surface which is engageable with a workpiece. The spikes or teeth can grip the workpiece to lock the fastener against relative rotation with respect to the workpiece.