Impact resistant solid vinyl frame and sash fully welded. 1/2-inch insulated glass. double paned. Both sash operate and are removable. Fully weeped frame for efficient water removal. Pre-punched nailing fin for added ease of installation. 1-inch J-channel slidin g return. Fully weather-stripped. True interlocking sash. Hook latch lock for positive sash to sash engagement. Includes full screen; Size 36-inch x 36-inch