Features Omni-Shield advanced repellency Techlite shoulder straps Backdraft ventilated back panel Integrated pack rain fly Dimensions Approx: 23" x 13" x 11" Description The Columbia Sportswear Ridge Runner 40L Backpack is that pack. The straps are made from Techlite, an ultra-light compound we borrowed from our footwear and molded around super-strong mesh inserts, with a soft cushioning layer on the interior for comfort. The result is unprecedented breathability and featherweight strength. When you're sweating it out on a steep uphill, your back will stay cool and dry thanks the Backdraft back panelfeaturing directional foam conduits that allow hot air to rise and be replaced by cooler air. Omni-Shield advanced repellency keeps the pack's contents dry, and specialized gear loops on the exterior front hold trekking poles and other essential gear. It's built to house up to a 3L hydration bladder.