Zero Gravity Windscreens Light Smoke Double Bubble Windscreen All Zero Gravity windscreens offer superior optical quality, strength plus flexibility, exceptional fit and finish, plus race-proven performance Developed by Zero Gravity R&amp;D in 1995 for Team ZGs race bikes, the Double Bubble is now seen on race tracks around the world Made from the finest grade of 1/8in. acrylic plastic. Each windscreen is stretched as it is formed, a process which results in superior strength and flexibility. This flexibility allows the windscreen to absorb road vibrations and resist cracking