Prime-Line 1 in. D X 0.25 in. L Nylon/Steel Spring Tension Roller Assembly 2 pk

This roller assembly with M-shaped tension spring with a 1 in. steel ball bearing roller is used by a variety of patio door manufacturers. The heat treated tension spring is 2-5/16 in. long and shaped like an M, giving it the tension needed by the screen door to slide properly. Easy to install.