4 Pack Sliding Screen Door Tension Spring Fits for M-Shaped Rollers, Replaces B 512, B 513, and B 746 Used on Both Top and Bottom, 1" Concaved Steel Ball Bearing

Compatible with Columbia and Uni-Fit series doors as well as a variety of other sliding screen door manufacturers for replacing similar spring tension rollers. | It has a 2-5/16 inch M-shaped tension spring and comes with a 1" steel ball bearing roller. | Installs by snapping onto the existing diecast door frame. | 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.