Prime-Line Products P 7521 Screen Retainer Spline, .165-in, 25-ft, Black Serrated for use in aluminum & fiberglass screening This product is manufactured in china 1/8 inch x 3/4 inch x 72 inch flat Steel bar stock Screen spline Serrated for use in aluminum & fiberglass screening 1/8 inch x 3/4 inch x 72 inch flat Steel bar stock Screen spline .165 diameter .165 diameter Serrated edges for better grip Black finish 25 foot length