Automatic Gate Lock (FM143) for Mighty Mule Automatic Gate Openers The Automatic Gate Lock provides peace of mind and added security for your single or dual gate. Unlocks and locks automatically as the gate is activated. Provides secure protection to withstand up to 2500 lbs. of force, providing stability and security. Easy DIY (Do It Yourself) installation for your Mighty Mule Automatic Gate Opener system. The Mighty Mule Automatic Gate Lock is compatible with all single and dual Mighty Mule or GTO/Pro Automatic Gate Swing Openers. Backed by a 12 month Mighty Mule Warranty and Technical Support.