The Integrity Wood Ultrex Sliding Patio Door from Marvin Windows and Doors is the perfect combination of beauty and toughness. Integrity doors are made with Ultrex®, a pultruded fiberglass Marvin patented that outperforms and outlasts vinyl, roll-form aluminum and other fiberglass composites. Ultrex and the Integrity proprietary pultrusion process delivers high-demand doors that endure all elements without showing age or wear. With a strong Ultrex Fiberglass exterior paired with a rich wood interior, Integrity Wood-Ultrex doors have both strength and beauty. Constructed with Ultrex from the inside out, Integrity All Ultrex doors offer outstanding strength and durability.