Alpha Series: Climbing and alpinism focused pieces: harness compatible length and waistline; chest pockets accessible while wearing a pack or harness; maximum articulation for overhead motions; helmet compatible hoods; drop hem; highest possible durability-to-weight ratio; emphasis on lightweight materials. SL: Super Light. Uses the lightest weight materials available to provide high weather protection, performance and/or packability, but with the right amount of durability. Carefully designed to be as light and packable as possible without sacrificing key elements required by alpinists and climbers, the Alpha SL delivers highly effective waterproof/breathable protection for sudden storms. By putting intense focus on design, fabric and feature selection, Arc teryx designers held the weight at 305g (10.8 oz), and allowed the jacket to easily pack into its own hood or included stuff sack. Features: Waterproof Windproof Breathable Lightweight Compressible and packable Micro-seam allowance (1.6 mm) reduces bulk and weight DWR finish (Durable Water Repellent) helps repel water from fabric surface Fully seam-sealed for waterproofness Narrow GORE(R) seam tape One-hand adjustable drawcords Anatomical shaping for fit and comfort Gender specific patterning Articulated patterning for unrestricted mobility Articulated elbows No-lift gusseted underarms Helmet compatible StormHood(TM) Laminated chin guard WaterTight(TM) external zippers Zipper garages to protect zipper closure from snow and rain Micro corded zipper pulls WaterTight(TM) full length front zip Laminated die-cut Velcro(R) cuff adjusters reduce bulk, and won't catch or tear off Adjustable elastic waist drawcord Laminated hem Drop back hem Harness HemLock(TM) inserts keep jacket in position under harness Chest pocket with WaterTight(TM) zip Note: Arc teryx WaterTight(TM) zippers are highly water resistant, but not waterproof. We do not recommend keeping items in your pockets that may be damaged by moisture Includes stuff sack with webbing loop to clip to a harness Trim Fit, with e3D patterning, Hip Length Weight: 305 g / 10.8 oz Activity: Rock Climbing / Ice Climbing / Alpine Climbing Material: N40r GORE-TEX(R) fabric with PacLite(R) product technology