We are taking the extreme durability of Ariat's classic Sierra boots to a new level with a puncture resistant sole for maximum protection in the workplace! ATS technology featuring a lightweight, composite forked shank offers optimal stability and all-day comfort. ATS footbed provides superior stability and cushioning. Puncture resistant, metal free SWEN-FLEX insole board delivers full protection without the weight. Heavy duty oil resisting and slip resisting Duratread outsole provides maximum wear resistance and heat resistance. Puncture resistant (PR) ASTM F2413-11 rated and ASTM F2413-11 MI/75 C/75 EH rated.