We proudly offer the PlyGem Premium and Pro series vinyl replacement windows. This line of windows was previously known as Great Lakes Window. It was founded in the early 1980's near Toledo, Ohio and was purchased by PlyGem in the mid 1990's. In 2009 PlyGem re-branded all of their acquisitions under the PlyGem name. Looking for stunning statements or smart solutions. Stand out with a stylish new look. Upgrade to a more energy-efficient option. Recreate the authentic look of an old window. Whatever your reason, when you're ready for replacement windows choose the ultimate in performance and luxury - choose Ply Gem Windows Premium or Pro series replacement windows.