Bulldog 028630 - Adjustable Channel Mount Trailer Coupler - 12,500 lbDesigned for utility, horse livestock, cargo, and construction trailer applications, BULLDOG Collar Lok Heavy Duty Couplers are the strongest in the industry. The BULLDOG design features the only automatic and continuously tight ball fit in the industry. A variety of coupler styles, tongue mounts, and latches allow configurations to match virtually any trailer. Adjustable couplers assure level operation for trailers when pulled by a variety of