Made with at least 40% of its weight in recycled materials, the Nike Air VaporMax 2021 FK incorporates recycled, ultra-stretchy Flyknit fabric (as well as a soft collar that conforms to your ankle) for breathable comfort. The stitched Swoosh and recycled TPU clip on the heel bring a touch of sparkle to your every step, while the VaporMax cushioning gives you incredibly flexible cushioning.