National Cycle's innovative VStream Windscreen gets its name from the unique shape and dimensional contours designed and engineered into the windscreen. The patented "V" profile helps push the turbulent wind out and away from the side of the rider's head, producing a quieter and more comfortable riding experience for both the rider and the passenger. VStream Windscreens are designed specifically for each model bike to ensure optimum performance and perfect fit using the OEM mounting hardware. Windscreens are made from the finest windshield material in the world, 4.0mm thick Lexan polycarbonate. This material is 20 times more impact resistant than acrylic or other plastic windshields, reason why National cycle gives a 3-year warranty against breakage. Additionally this polycarbonate features National Cycle's exclusive Quantum coating. This provides 10 times better scratch resistance than any other windshield material on the market. The Tall and Standard sizes are outstanding high-speed highway performers for FLHT/FLHX riders. Enjoy a significant improvement in wind management and riding comfort. If you want a custom look and a lower profile, you will like the performance of the VStream models in Low or Ultra Low. Height is measured from the bottom to the top on the center of the screen.