"The Collar" Trailer Hitch Lock for Bulldog-style Couplers (Including the RAM) Protects Against Trailer Theft & Unauthorized Use Security While Attached To or Detached From A Vehicle Heavy Duty Stainless Steel Body Resists Cutting, Grinding and The Elements Works With All Bulldog and Ram Latch Styles As Well As On Many Butler and Kodiak Couplers Made in the U.S.A