The Sierra work boots by Ariat are mountain-tough. The most durable platform on the market combines with Ariat's secure, comfortable ATS system. ATS technology includes a moisture-wicking footbed, a gel-cushioned footbed with heel stabilizer, and a lightweight, ergonomic composite forked shank to enhance stability. This oil and slip-resisting sole provides extreme heat and abrasion resistance. Premium full-grain leather upper, Goodyear Welt construction, ergonomic support and cushioning, this heavy-duty boot delivers.