The Flex SideShield from Bouton is a welcomed addition to many safety glasses. These sideshields are molded to a bendable softness, but are still rugged enough to absorb the energy from an impact or flying debris. The sideshields still allow safety glasses to fold up correctly for proper storage. They are easy to install, because they require no tools or parts - simply weave through the safety glasses' temple. Flex SideShields block 100 percent of harmful UV rays, and meet ANSI Z87.1 standards.