evo.com | Arc'teryx Day Packs > This is Arc'teryx's smallest Alpha FL pack, built for climbers who subscribe to the less-is-more philosophy. The Arc'teryx Alpha FL 20 Backpack combines Hadron AC^2 LCP fabric (that's Liquid Crystal Polymer for the nerds) with a minimalist 24-liter design perfect for summit pushes and streamlined alpine objectives. Lightly padded shoulder straps and a laminated back panel keep things comfortable, while the external bungee system compresses your load and secures crampons or an extra layer. 57cm Length x 27cm Width x 18cm Depth 315d Hadron(R) AC^2 Nylon with Hadron(R) Light, ultradurable, and waterproof. Internal Security Pocket External WaterTight(TM) Zippered Pocket with Key Clip Lightly Padded Thermoformed Shoulder Straps Durable, light, and comfortable. | Arc'teryx Alpha FL 20 Backpack 2027 - Regular in Black | Nylon