The Kith x adidas 4D Runner Aspen is a limited edition collaboration between Ronnie Fieg and adidas Consortium that brings back the famous Aspen colorway in a new way for 2018. First seen on a premium adidas release from Fieg in 2016, the striking multi-color Primeknit weave incorporates dark red, white, and grey shades. On the 4D Runner, the pattern is used on a mid-top upper that sits above adidas's innovative 4D midsole technology in its signature mint-green hue. Released in extremely limited quantities in November 2018, the Kith x adidas 4D Runner Aspen is one of the years most sought after models for Fieg and adidas fans. Purple