Integrity wood and Ultrex fiberglass composite windows can be specified to extremely tight tolerances, allowing orders in 1/64-inch increments to fit even the most difficult projects. The wood/fiberglass material is eight times stronger than vinyl and three times stronger than wood-vinyl composites, the manufacturer says. It also will not scratch, warp, or corrode. Integrity by Marvin Windows and Doors, 888.419.0076; www.integritywindows.com.