Make your tow vehicle and trailer more secure by keeping them locked up tight with a CURT hitch and coupler lock set. This three-piece set includes a hitch lock, coupler lock and trailer coupler lock, so whether you are towing or storing, you can keep your trailer more secure. Like a hitch pin and clip, the hitch lock is designed to insert into the hole in the side of a receiver tube to hold a ball mount or hitch-mounted accessory in place. It features a pin diameter of 5/8" to fit 2" receiver tube openings. Likewise, CURT coupler locks are designed to add security to your trailer and towing equipment. Instead of merely retaining the coupler latch mechanism, they lock it into place and act as a theft deterrent for your trailer while it is coupled to your vehicle. This coupler lock features a pin diameter of 1/4" and fits any coupler span from 1/2" to 2-1/2". This set of three locks also includes a trailer coupler lock to deter theft of your trailer while it is parked and left unattended. The lock mounts over the coupler and prevents a trailer ball from being inserted into the coupler opening. This trailer coupler lock is able to fit 2" and 2-5/16" flat lip couplers. It is constructed from lightweight, rust-free aluminum and has an anodized aluminum finish. For the ultimate in 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. Also for added convenience, all three locks in this lock set are keyed alike. For your boat, ATV or camper, keep your toys more secure with CURT locks.