Enjoy the comfort, performance, and beauty or our highest rated Vinyl Double Hung window system. The 500 WindBlocker Series Vinyl Double Hung is manufactured utilizing the “best of the best” components offering the highest level of comfort available in a Vinyl Double Hung window system. The 500 WindBlocker Series features our Ultra-flect Glass package known for achieving an amazing “Center Of Glass” R-value of five. When it comes to selecting windows for your home you will not find a finer product than the Windblocker 500 Series. We offer styles and options to fit any architect requirements both contemporary and classic.