Buyers Products Adjustable Cast Coupler with 5 Position Channel Model 0091545Buyers Products Adjustable Cast Coupler with 5 Position Channel Model 0091545 The Adjustable Cast Couplers with 5 Position Channel from Buyers Products provides added flexibility in coupler height for leveling your trailer. Its spring loaded auto engage latch lets you quickly lock it to a hitch ball with just one hand. The latch can be pinned opened for ease of uncoupling. The 5 position channel allows height adjustability for leveling your trailer.