CURT class 3, or standard duty, ball mounts are a step up from classes 1 and 2. They feature a 2 Inch X 2 Inch shank and have a higher weight capacity for towing heavy duty trailers, features utility trailers, boat trailers, campers, single horse livestock trailers and most recreational vehicle trailers. With class 3 trailer hitches being the most common type of trailer hitch for pickup trucks and SUVs, the class 3 ball mount, by association, is an excellent complement to this trailer hitch and these larger vehicles.