The best-selling TITLE Boxing Adjustable Doorway Sit-Up Bar is back and better than ever! The Doorway Sit-Up Bar easily attaches to the bottom of any standard door with a rubber lock mount to help prevent damage to the door while you target those key core muscles. Your new favorite work out tool is the perfect size to throw in your gym bag for use on the road, at the gym or at home so you never have an excuse not to work on your abdominal muscles so you can withstand even the most vicious body shots.