All skylights are made of high perform- ance thermoformed polycarbonate to be long lasting and easy to clean. When choosing a skylight, measure your rough hole opening and overall exterior size. There is a size to replace most manu- factures original equipment. All skylights include care and installation instructions on the box All exterior skylights include a tube of approved urethane sealant that must be used when installing. Interior ceiling domes come in two models: Windowed or Non-windowed. Others sizes available as special order. Color: White