Mighty Mule Gate Operator Security Pin Lock (FM133) Protect your property and gate operator from theft with the Mighty Mule Gate Operator Security Pin Lock. Substitutes the factory pin at the front-end mount of all Mighty Mule/GTO Pro swing gate operators for enhanced safety and security. Easy DIY (Do It Yourself) installation for your gate system. Includes two keys to unlock the Pin Lock for removal. Dual gate systems require two Pin Locks. Backed by a 12 month Mighty Mule Warranty and Technical Support.