This CURT adjustable channel-style ball mount has a shank size of 2" x 2" and features a ball and pintle combination to accommodate a 2-5/16" trailer coupler or a lunette ring with an inside diameter of 2-1/2" or 3". It also features an adjustable shank assembly with multiple mounting holes for varying ball heights. It can be raised to a maximum of 5-1/4" rise or lowered to a maximum of 6" drop, allowing you to make your trailer completely level in any towing situation. The channel-style design and dual-pin mounting system also provide a built-in anti-rattle feature to eliminate obnoxious chucking noises. This CURT adjustable ball mount offers a gross trailer weight capacity of up to 13,000 lbs., allowing you to tow a variety of heavyweight trailers (limited to lowest-rated towing component).