You won't be wearing these flame resistant jeans to any high fashion parties, but you won't want to wear anything else when you're on the job site. That's because they're made with 100% 405 gram flame resistant cotton denim. This stuff is like anti fire armor. It's designed to not ignite, and it won't continue to burn. All of the stitching is done with 13 ounce aramid high tenacity flame resistant thread. Aramid fibers are fireproof and strong, so these Wolverine jeans won't have any weak spots. Wolverine designed this flame resistant workwear so that all of the metal is thermally protected from your skin. In addition, the metal zipper also come with fireproof aramid tape for extra durability. Since you'll be working hard, you need them to be as functional as the seven belt loops that give you a secure fit. Another tool pocket on the right side, below the back pocket, is the perfect spot for pliers, a screwdriver. With all these fire beating features, it's no wonder this Wolverine workwear meet a variety of safety standards. Standards: HRC2. Arc Rating: ATPV 16.4 cal/cm2. NFPA 1975-2009, NFPA 70E-2004, ASTMF 1506-2010a, et OSHA 29 CRF1910.269, CAN/GSB 155.20-2000, CAN/CGSB 155.22-97, EN ISO11611:2008, EN ISO11612:2008, EN ISO14116:2008. This garment meets the requirements of NFPA2112-2012 standards on flame-resistant garments for protection of industrial personnel against flash fire, 2012 edition.