capucha sparco rw 4RW 4 The RW 4 baselayer line is designed for comfort and protection. The RW 4 features a soft touch interlock fabric. Then, RW 4 includes long sleeved baselayers, long johns, a single vent hood, and mid calf socks. Hoods are one size fits most; baselayers and baselayers are available in sizes Small through XX Large. RW 4 baselayers and baselayers are regular fit. Socks are available in sizes 38 39 through 46. The RW 4 line is FIA 8856 2018 approved.