ESS 740-0536: Highlighting streamlined frames and lenses designed to prevent fogging, the ESS FirePro-1971 structural firefighting goggles set a new industry standard. Compliance with the Nfpa 1971-2013 Edition, which includes a 5-minute, 500F oven test, ensures the high quality of this product. The goggles also meet U.S. Federal Osha standards and surpass the requirements of Ansi Z87.1-2015. They are recognised as Primary Eye Protection by Nfpa 1500.All the parts of the ESS FirePro-1971 goggles are constructed to be resistant to heat and flame. The FirePro-1971 EX-2 variant boasts a two-part strap equipped with Snap-on/Snap-off mounting brackets for effortless attachment to brimmed helmets, eliminating the need for drilling.