Pentax 6x7 Lens to Canon EF Adapter

Adapter for mounting Pentax 6x7 lenses on Canon EF mount DSLRs. Locks the camera and the lens in position. Line the red dot on the lens with the small dot on the mount and turn to the larger dot until it locks.

1x 25mm M3 screw and nut
Half a spring from a pen.

Empiricus@Dremomys