Product Description This screen retainer spline is constructed of top quality vinyl that is round in shape. It features a hollow core center, it is serrated on its exterior surface, and it is gray in color. Vinyl screen retainer spline like this one is used to hold fiberglass and aluminum screen material to screen frames of both windows and doors. This retainer spline has an outside diameter of 0.250 inch (1/4 inch) and measures 25 ft. in length. From the Manufacturer This screen retainer spline is constructed from vinyl. It features a round hollow serrated core. This type of spline is used to hold screen material to window and screen door frames.