Master Lock® Coupler Locks provide reliable theft protection for your unattended trailer.
Install one and rest easy... these babies make it almost impossible for anyone to drive off with your trailer while you're away. Fits on front of trailer coupler to prevent hitch ball access. Rugged, die-cast zinc body resists corrosion. 4-pin cylinder tumbler.
State Size, as available in the Shopping Cart.
- Fits: Acme, Big Boy, Fulton, Hammer Blow, Ideal and Lainson 1 7/8" couplers
- Fits: Valley 1 7/8" couplers, Acme, Big Boy, Fulton, Dico, Ideal, Lainson and Valley 2" couplers
- Fits: Marvel MC-683, MC-883, MC-939, MC-970, Lainson 2" and 2 5/16" couplers
- Fits: Fulton 33-305, 34-300, 34-308, Valley 5125, 5135, 5136
- Fits: Hammer Blow 1B, 2B, Lainson 76