Easily convert your 2" tow ball to a 2-5/16" tow ball without any tools this Weigh Safe Tow Ball Clam Shell. This simple to use Clam Shell easily installs right over top of your 2" ball and allows the user to tow trailers with 2-5/16" couplers. When you have completed towing, simply remove the Clam Shell and stow away for another day.