CZC AUTO Trailer Hitch Coupler Locking Pin Design：1/4 Inch diameter tongue lock pin with effective length 3/4 Inch. Small size for easy carrying. Keeping the coupler lock in your pocket or vehicle anywhere that is fine. Please verify dimension and length of the pin you want before purchasing our coupler hitch lock pin. How To Operate Our Trailer Tongue Coupler Lock: Spinning the flat key 5-7 times to open or close the hitch lock. Security Of Our Coupler Locking Pin: This trailer lock is made of high-strength steel to deter theft. The hitch lock is coated with black electrophoretic paint to prevent corrosion. Coupler Locking Hitch Pin’s Application: Tow Trailer Boat RV Truck Car CZC AUTO – A Reliable Brand In Hitch Sercurity Industry: We offer 30-day money-back guarantee for any reason, 12-month warranty for quality-related issues. If you have any question after receiving or using our trailer tongue lock, please contact us, your problem will be solved within 24 HOURS.