MCGARD Anti-theft device/nut for outboard motors 5/16′-18

Theft Protection for Outboard Motors. McGard outboard motor locks are designed to lock the outboard onto the transom of the boat. Simply replace one of the mounting nuts with a McGard locking nut. McGard outboard motor locks are identical in quality and construction to our stern drive locks. A free-spinning collar turns if attacked by gripping tools, protecting you against costly outboard motor theft and the resulting inconvenience.