2006 Nike Air Dual-D Firm Red/White/Silver

Condition: Overall solid. Wearable with lots of life left.

Size: 11M

Release Year: 2006

The Air Dual-D has one of the more memorable midsoles from mid-2000s runners. Its standout two-tone design is on full display with this pair, featuring a striking deep red on the inside portion of the midsole. Nike used Phylon to form the sole, which at the time was considered lightweight, highly flexible, with strong construction and good compression.

The conventional "phylon process" consists of a two part foaming process involving: 1) heating and expanding the formulation (foam pellets supplied by a chemical company) in a press, to create a block of foam; 2) After, the foam is cooled then put in a compression mold and heated again to get the desired shape of the midsole.