The Boost Sport BirkSun Glacier White Backpack with built-in battery pack is built for those with an active lifestyle that crave adventure. Completely redesigned with premium, water-resistant fabric and 100% waterproof solar panels. The BirkSun Sport collection comes equipped with a built-in battery that stores enough power to recharge a smartphone up to 1.5 times! The battery inside the Boost Sport will be continually charged anytime the solar panel is exposed to sunlight. Your new best friend at the beach, music festivals, and during international travel. Pack it, wear it, charge it, and make it your own. Dimensions: 18.5″(H) x 13″(W) x 8.5″(D) / 2.4 pounds.