Designed to fit between 24 inches or 16 inches on center cross members and hold your front wheel in place. Please make note, recessed wheel chock is not designed to have your wheel sit down in the well, the well is there to lower the cover into when not in use, making them flush with your trailer floor. 2 inch recessed pan makes ideal storage area for tie-downs. Folds down out of the way when you have other uses for your trailer. Made from heavy-duty 1/8 inch steel construction with powder coated black textured finish for years of use. Mounting hardware included. 5 year warrenty. Over all size 24 inch = 24 x 9inches. Cut out size 24 inch = 20- 1/8 x 7- 1/4inch.