Model 4000 Patio Doors Your neighbors will think you spent a fortune on these doors – let them! Designed for remodeling, these sliding patio doors are both attractive and affordable. These doors utilize multi-chambers of insulating air that keep heat and cold outside, while adding to the door's overall strength. The sliding patio doors are available in either full-glass or gridded styles. The classic look of multiple panes is created with optional, internal, dust-free muntins. These grilles are inside the glass, so you never need to clean them. Frames and panels are easy to maintain and will never need painting. Discover the value of our sliding patio doors – designed to last, pleasing to the eye and energy-efficient. Available in standard widths with side-lite and transom options. FEATURES Full 4-9/16 inches wall thickness. Optional Dust-free muntin (DFM) internal grille system. Glass glazed in silicone. Units have full-length, uninterrupted, interlocking meeting rail for positive contact and a tight seal. Fixed panel held into place with exclusive lock blocks. Standard painted lockset with wood pull handle or optional polished brass set. Available with or without nail fin. Dual tandem rollers travel on stainless steel track cover for effortless smooth-sliding operation.