Bulldog trailer couplers are the standard by which all others are measured. No other competitor offers the combination of Heavy-Duty materials unique features and replaceable parts for outstanding performance and long life. That’s why Bulldog is the right selection for your Heavy-Duty towing needs whether its utility hauling horses and livestock cargo or construction trailer applications. Bulldog is the most trusted name in trailer couplers and our adjustable trailer couplers are no exception. For over 80 years Bulldog has been building that reputation with a number of innovations that have enabled it to stay out in front of the completion. Designed for the most rugged applications like horse and livestock hauling utility hauling and construction trailer use these couplers are the strongest in the industry. The Bulldog adjustable height coupler is available in either a Wedge Latch® style or Channel Mount style. The channel mount adjustable height coupler also offers a range of height adjustments to assure level operation when an individual trailer is pulled by a variety of vehicles. Collar Lok technology ensure a continuously tight ball fit an industry exclusive. Trailer Coupler Adjustable Lock Nut For Proper Ball Tension Locking Hole In Coupler Handle Positive Locking Trigger. Clear Visual Indication Of Proper Closure Channel Mount Style. Strong In Both Static And Dynamic Loading Conditions Offers A Range Of Height Adjustments To Assure Level Operation When An Individual Trailer Is Pulled By A Variety Of Vehicles