The Chippewa Thunderstruck work boots are made to get the job done. Working on hot days is no problem because these boots are designed to keep you cool with their non-insulated construction. They have Ortholite Removable Insert Insoles that adapt to the unique contours of your feet to deliver custom comfort. And because the foundation of a great work boot comes down to a tough outsole, these boots have been engineered with Vibram's Thunderstruck TC4 Plus outsole, powered by TC4 plus rubber and co-molded urethane midsoles for superior traction and maximum shock absorption. Metallic shanks have been embedded within the soles to offer unmatched support, ensuring you stay steady and focused no matter what terrain you are working on. Chippewa. The Best. By Far!