Make your tow vehicle and trailer more secure by keeping them locked up tight with a Curt hitch lock. Like a hitch pin and clip, a hitch lock is designed to insert into the fastener hole in the side of a receiver tube in order to hold a ball mount or hitch-mounted accessory in place. While a Curt hitch pin does offer sufficient strength for keeping your ball mount firmly attached, a Curt hitch lock goes one step further. Curt hitch locks allow you to lock your ball mount into your trailer hitch, deterring theft and preventing anyone from detaching your trailer at the ball mount and towing away your property without your permission. This Curt hitch lock features a barbell design and comes with a 5/8" pin diameter to fit a 2", 2-1/2" or 3" receiver tube size. For the ultimate towing security, a hitch lock and coupler lock used together will provide security at both the vehicle-side and trailer side of your towing setup. For your boat, ATV or camper, keep your toys more secure with Curt hitch locks.