Nike ACG Lunarterra Arktos - Men'sIntroducing the Nike ACG Lunar Terra Arktos, an innovative sneaker boot. The upper consists of leather and Hyperfuse with Flywire technology that houses a warm removable innersleeve. This innersleeve sits on a Lunarlon cushioned midsole for optimal comfort. The aggressive outsole pattern provides excellent traction with its sticky rubber and forefoot grooves. Wt. 21.5 oz.