4 Pack Sliding Screen Door Tension Spring Fits for Academy Doors, Replaces B 638, B 687, B 639 and B 756 Used on Both Top and Bottom, 1" Concaved Steel Ball Bearing

Compatible with Academy, Metal Industries as well as a variety of other sliding screen door manufacturers for replacing similar spring tension rollers. | 1-3/4" heat treated V style tension spring with a 1" steel ball bearing roller. | When installed the bent, or angled, flat spring positions the roller assembly so that an adjusting screw adjusts the height of the roller as needed. | 4 pack included used on the top and the bottom of the sliding screen door, we recommend replacing all 4 rollers on single door panel at the same time. | Note that no mounting screws included in the package, please kindly reuse your old ones.