Ultra-light and packaged for the extreme, the Arc'teryx Alpha SL Pullover - Boys's is Built with GORE-TEX PacLite, is fully H2Oproof and provides excellent ventilation without sacrificing Safe guardion thanks to a full-length separating side zip. The lightest, most packable H2Oproof shell in Arcteryx Ascent collection, the Alpha SL is equipped with a helmet compatible SpeedHood, H2OTight zippers, and gusseted underarms for no-lift movement. Ideal for your next summit bid or as an emergency shell on your summer backpacking trip, the Alpha SL is a reliable source of H2Oproof Safe guardion.