Four years ago I purchased 11 windows for my home in Middletown, New York. Mark Four sold and installed the windows,which came with a ten year 100% replacement or repair warranty on the hermetic seals. However, this year three of the seals failed and Mark Four refuses to replace them without cost to me. They want to charge me $432.oo to fix them. Since my windows are under warranty there should be no charge to fix the defective seals. Don't trust this company I payed a premium price of over $7,000.00 dollars because they are a Sears Authorized installer and warrantied the job.