BLOCKS HUMIDITY FOR UP TO 8 HOURS. An iron's best friend, this lightweight hairspray delivers advanced protection from heat styling and locks in looks with soft hold and shine. It forms a protective barrier between hair and tools with our exclusive HeatCTRL® complex, a heat-activated blend of proteins and silicones that help resist humidity and block out frizz. How to Use: Spray onto dry hair before using heat styling tools to help protect from damage. Then reapply to lock in the shine and the look.