Perfect all-around commuter or trail pack that expands on demand for greater flexibility. With one zip of the expansion panel, your overall cargo volume expands over 40%. And whatever you're carrying, the air-mesh harness, hip belt and adjustable sternum strap keep your load well-balanced and comfortable. Media pocket protects your smartphone, iPod, camera or other devices while keeping them close at hand. Reflective back strip with tab to click on a blinker for early morning and evening safety. 2L Antidote reservoir keeps you well hydrated. Dimensions: Open: 19.25 X 8.875 X 9.5 in. Closed: 19.25 X 8.875 X 7.25 in / Open: 49 x 22.5 x 24 cm. Materials: air mesh with slider sternum strap.