Klymit Stash 18 Air Frame Day Pack MOST VERSATILE PACK ON THE MARKET: Ideal backpack for day hiking, biking, and around town MOLDS TO YOUR BACK: Features Air Frame technology for a customizable carry and comfort with great lumbar support CUSTOMIZABLE COMFORT: Integrated pump located on the shoulder strap allows you to adjust the pressure on the move for full load transfer and stability FEATURES: Sternum Strap, Hydration compatible, Removable Air Frame (doubles as sit pad) SPECIFICATIONS: Ultralight Weight: 12.38 Ounces! Volume: 18 L - Because we are authorized sellers of this products, it includes a limited LIFETIME WARRANTY