Retainers can be made and modified on site and on demand with HP Accu-Lock® Retainer Inserts by Wilson Tool International. HP Accu-Lock® simplifies the use of special retainers by eliminating the need for complicated jigs, inspection fixtures and specialized knowledge to machine ball holes into the punch plate. In fact, HP Accu-Lock® eliminates the ball hole. Punches are held securely in place with a straight-line machined hole that can easily be created in-house.