INTERNATIONAL STANDARDS — Meets ANSI Z87.1 (US), CE EN166 (Europe), CSA Z94.3 (Canada), AS/NZS 1337.1 (Australia and New Zealand), UKCA (United Kindom) IMPACT RESISTANCE (AT EXTREME TEMPERATURE) - Made of extrusion-grade polycarbonate, our face shields can withstand the impact of a 6 mm steel bead traveling at a speed of 268 MPH at extremes of temperatures (from -23°F to +122°F). IMPACT RESISTANCE (AT ROOM TEMPERATURE) - Tested hundreds of times in the lab, our face shields can withstand impact of 6mm steel ball traveling at a speed of 300 MPH easily. BEST OPTICAL QUALITY - Tested by ANSI Z87.1 (All Optical Requirements are PASSED) and CE EN 166 (CLASS 1 Optical Level is PASSED). ALUMINUM REINFORCED EDGE - Aluminum edge Increases the Strength of Visor, and allows user to adjust a suitable curve for working. RATCHET HAEDGEAR - Easily adjusting the headgear to loose of fit by rotating the knob. RAPID VISOR REPLACEMENT - User can replace the visors within one minute (1 FREE replacement visor is included in the package).