ALLBEST windows utilize high-grade polymer window and door frames from European quality. Our frames are steel reinforced for additional strength. These frames are unplasticized polyvinyl chloride (PVCu), resulting in a stronger and longer-lasting frame. Which are strong and do not discolor sunlight, this in conjunction with modern glass, first-rate insulation values can be achieved. For saving energy, PVCu windows are a perfect choice; independent of climate and region.