SharpTruck has a variety of trailer balls to suit your needs. A trailer ball, also referred to as ball or hitch ball, is a ball-shaped attachment to a hitch onto which a trailer coupler is attached. The coupler mounts and locks on top of the trailer ball. Trailer balls come in a range of sizes including 1 7/8", 2", 2 5/16" and occasionally 3". In general, lighter trailers use smaller diameter trailer balls, be sure to check the proper size needed to fit your application. The size and rating of the trailer ball is just as important as the rating of the trailer hitch.