Part ofOakley's Ballistic ALPHASystem M Frame Alpha Ballistic Glasses are designed to maximize both comfort and protection. Like M Frame 2.0 the M Frame Alpha features comms friend temple arms and a clip that securely holds the lens in place. Because the M Frame Alpha is designed for the world's most elite warriors it's fully compliant with ANSI Z87.1 and MIL-PRF-32432 requirements for high-mass and high-velocity impacts. The M Frame ALPHA is compatible with the SI Helo Gasket that offers additional protection by creating a seal that blocks high velocity air dust sand and debris that is generated by rotary wing aircraft during infil and exfil operations.Features of Oakley Ballistic M Frame AlphaPermanent Anti-Fog Lens Coating - Anti-Fog Recharge Kit IncludedDistortion-Free High Definition OpticsHydrophilic Unobtainium(TM) NosepadProtection Against Sand Wind and DustANSI Z87.1-2003/2010 and MIL-PRF-32432 Rated