The easy to install Mace Door Brace is an effective preventative tool against a break-in at your dorm, college apartment or hotel room abroad. The Mace Big Jammer is made from strong 20-gauge steel and installs quickly providing you with added security. Easily adjusts with the push of a button to fit most hinged doors. Rubber end caps prevent the door brace from slipping but are removable for use on sliding glass doors as well.