In August of 2005 I purchased 11 windows manufactured by Alside out of the eleven 3 had hermetic seal failures. The seals all failed at the same time four years after my purchase. Don't buy Alside Windows the quality of their hermetic seals are poor. There is no charge under the warranty for replacement parts or materials. However, there is a labor charge on each window for removal and installation to replace the defective parts. The labor cost I was quoted for the three windows is $432 dollars. More of my money, because of inferior parts and materials used in their product. Again don't buy Alside Windows.