The Free RN Flyknit 2018 was the lightest in the Free RN lineup at the time of its release, designed with a barefoot-feel in mind for runners. This Nike Wmns Free RN Flyknit 2018 ‘Guava Ice’ sneaker incorporates a sock-like upper that includes more stretch yarns than its predecessors for a closer fit. This women's shoe includes a revolutionary sole that expands and contracts with every movement for a natural feel.