Reese Interlock™ hitch tow balls are designed for use with Interlock™ Ball Mounts. Each tow ball has a patented hexagon-shaped base that fits in a matching hexagon in the ball mount, so you can tighten the ball with just one wrench. No more scratching and marring your hitch ball when tightening. Interlock tow balls may also be used with standard ball mounts and drawbars, but 2 wrenches will be required for installation. The Reese tow ball is solid steel with a polished chrome finish.