The RELIABILT 105 Series New Construction Single Hung Window boasts top performance at an affordable price. Its bottom sash is easily removable and operates using dual lift rails. Ideal for both new construction and remodeling, this window features a pre-punched, integrated nail fin and built-in accessory channels for various installation options (Series 3050 is available without a nailing fin). With a DP-50 rating for windows up to 36 inches wide by 74 inches high, this modular window makes calculating rough opening widths for multiple units a breeze. It also features Low-E glass to reflect solar energy and the added thermal efficiency of Argon insulating gas. The 5/8-inch contoured grid pattern between the glass panes adds style to your home without creating the extra cleaning complexities of exterior grids. (Please note that ENERGY STAR qualifications may not apply in all zones. Refer to each window's U-Value and SHGC value for exact specifications.)