The TowSmart Heavy-Duty Coupler Lock protects your boats, campers, trailers, equipment, and other valuable assets from theft with its 9/16 in. heavy-gauge locking bar and fine-tooth adjustment. It features a round key locking cylinder for greater security and theft deterrence. The Coupler Lock is designed to fit 1 7/8 in., 2 in., and 2-5/16 in. couplers and provides multiple locking positions. Simply slide the ball into the coupler, connect the heavy-duty shackle, and use the included key to lock into place. It is easy to install, provides a tight and secure fit, and is made of corrosion-resistant materials designed to withstand harsh weather conditions. The bright finish on the TowSmart Universal Coupler Lock is highly visible to discourage others from tampering with your trailer. Material: Steel.