GD52199 Galvanized steel disc is used to drive the door lock bars. Accepts a 0.31" square shaft handle (GD-52121), acts as a keeper or GD-52119 center mount deadbolt lock. You may wish to stock these related parts: GD-52119, GD-52121, GD-52139. Features: -Lock bar disk. -Material: Steel. -Diameter: 3.75". -Dimensions: 9.5" H x 4.81" W x 0.75" D.