The Castelli Flanders 2 Warm Long Sleeve Women\'s Base Layer will keep your temperature regulated well below freezing – if you\'re cycling in the biting cold, this is a solid investment.Bred from cold February starts in Flanders, this base layer is primed for your winter training, commuting and even off the bike excursions.The SottoZero fleecing is high-loft and luxuriously soft on your skin whilst also retaining great moisture-management properties. Underarm mesh inserts, flat-lock stitching and a contoured fit finish this dedicated cycling base layer.Key Features100% Polyester SottoZero fleece multi-denier,Flat-lock stitching, underarm mesh and contoured fit,Temperature range: -4°c – 10°c.