Our Sierra platform delivers extreme durability and high heat resistance with advanced stability and cushioning. It's the ideal platform for harsh outdoor jobs, high heat environments or intense construction work. -ATS® technology provides ergonomic support on uneven terrain -Premium full-grain leather -Removable All Day Cushioning insole -Oil- and slip-resistant Duratread™ sole provides maximum wear resistance -High heat-resistant sole -Goodyear welt construction -Six-row stitch pattern -ASTM F2413 M/I/C EH rated