Spectra’s Armour Lock Gutter Guard’s unique pressure fit design will keep leaves and other debris out of your gutter system. The easy 3 step installation process takes just minutes to complete. Armour Lock Gutter Guards are compatible with metal, tile, and asphalt roof systems. Now available in both 4 and 6 foot lengths. Spectra Metal Sales, Inc. uses the Aluminum Association’s standards and/or National Coil Coating Association as guidelines for the physical testing of the material.