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.