BOLT 7018446 5/8" Receiver Lock for late model Chevrolet, GMC, Hummer, Buick, Cadillac, Potiac and Saturn Keys Opens with your vehicles ignition key eliminating extra keys on your ring; Works with late model Chevy, GMC, Buick & Cadillac keys. Please verify fitment by looking up the year, make and model of your vehicle Stainless Steel 5/8" diameter pin for use with Class 3, 4, and 5 hitches (2 to 2.5" Receiver) Auto-Return spring locks automatically when key is removed Stainless steel lock shutter to keep out dirt and moisture, plate tumbler sidebar to prevent picking and bumping, double ball bearing locking mechanism Limited Lifetime Warranty. Refer to Other Content PDF attached below in Technical Specification for Fitment