XSG Ballistic passes MIL-PRF-31013 Ballistic Standards.Strap has Quick Fit retainer for easy on/off. Design allows air to flow freely reducing heat. XS EASE Replacement lens system. Lenses provide 99% protection against harmful UV rays. Exceeds ANSI Z87.1-2003 High Velocity Impact standard. Lenses are treated to prevent fogging, scratching, and static. Flame resistant foam padding forms a seal to keep out dust and airborne particles. Kit includes Frames with strap, clear, amber and gray ballistic lenses, interchangeable temples, and black ballistic nylon storage case. Sold by the dozen.