KEEN Utility Men's Kansas City Mid Carbon-Fiber Toe Work Boot Black/Gun Metal Built on a versatile, all-purpose outsole and featuring our KEEN.ReGEN energy-returning midsole, this carbon-fiber toe work boot is a standout on variable jobsite terrain. Incorporating KEEN.BELLOWS FLEX technology for easier bending, kneeling, and flexing where you need it most and KonnectFit heel retention for a locked-in feel, it'll keep you productive all day long. KEEN Utility Men's Kansas City Mid Carbon-Fiber Toe Work Boot Black/Gun Metal