This premium heavyweight laminated shingle is composed of a dimensionally stable non-woven glass fiber mat, which is thoroughly impregnated with stabilized waterproofing bitumen. Cambridge® IR is distinguished by its random shake-look design, unique dual band shadow coloration, and superior thermally activated shingle sealant. Colored, ceramic granules surface the tops of both layers of this shingle to protect the asphalt from ultraviolet radiation. Special algae-inhibiting granules have been added to provide long-lasting algae resistance. Each shingle has release tape and mineral powder applied to the underside, thus preventing any sticking in the bundle.