Black Diamond NFPA Structural Lug Sole Kevlar Lined Insulated Firefighter Boots Made in USA NFPA certified Structural rubber Kevlar lined and insulated FF boot. The last used to construct these boots has been designed for maximum comfort and accurate fit. In addition, the Enersole System includes a high-density polyurethane midsole that absorbs energy. The second layer of comfort an open cell OrthoLite footbed that provides long lasting all-day comfort. The footbed is anti-microbial, anti-bacterial and fast drying. This boot features a durable rubber pull on system, a triple ridge steel shank for support, a stainless teel midsole, a steel toe that meets ASTM standards, a tibia protector for additional shin-guard protection, and a Kevlar/Nomex lining as well as 6.0 mm of open cell foam insulation. The molded rubber outsole is a one-piece K-lug design for maximum traction. This boot is NFPA 1971 certified.