Miller 415 D Bolt anchorage connector is designed specifically to prevent roll out, the Miller 415 D bolt anchor is an easy-to-install anchorage connector that can be mounted in a variety of positions and is ideal for use with Miller shock-absorbing lanyards or Miller retractable lifelines. 3/8" diameter bolt. Miller® 415 anchorage connectors meet or exceed all applicable OSHA, ANSI or CSA requirements.