Item Type: Trailer Coupler Lock Material: Aluminum alloy, alloy steel. Package List 1 x Trailer Coupler Lock 1 x Pin 1 x User Manual 1High in Security: The U shaped trailer lock installed on the coupler of trailer tongue can protecting the truck or trailer from theft and prevent picking up, prying and drilling. 2Combination Lock: The hitch lock has 4 digit combination password design, and the default password combination 0000 can avoid forgetting the key to ensure better vehicle safety. 3Universal Design: The universal trailer hitch lock is designed to be adjustable with 11 locking positions and can be fitted with 1-7/8in, 2in and 2-5/16in couplers, very useful. 4Premium Material: Combining premium aluminum alloy and alloy steel materials with sturdy structure, the trailer coupler lock is not likely to deform, and durable for long using. 5Better Visuality: The anti theft trailer lock with bright yellow color can provide high visibility trailer protection, which is an essential accessory for all types of trailers.