This is a Multi-Spline screen retainer designed with 3 sizes on one roll. Easy to separate the individual sizes. One roll has 0.120 in., 0.145 in. and 0.165 in. to be used for installing various types of screen fabric into a window screen or screen door frame. Regardless of the size of your frame channel, this one roll will allow you to insure a secure installation. It is a top-quality round, serrated vinyl with a hollow core.