Energy efficient 1/2" Low-E insulated glass. R-value 2.86; U-value .35; SHGC .40. Includes full screen. Extruded vinyl, fusion welded frame. Fully weeped frame, for efficient water removal. Both sashes are operating and removable. Fully weatherstripped. Hook-latch lock for positive sash-to-sash engagement. Pre-drilled installation screw holes. Proudly made in the USA.