Used for bicycle commuting. I'm selling it because I've switched to the train. It's comfortable to use in the summer as it prevents your back from getting sweaty. deuter Race EXP Air Brand: deuter Aircomfort System ● Expandable ● Valuables pocket ● Built-in rain cover ● 3.0L hydration system compatible ● Stretch compartment ● Helmet holder ● Shade holder ● External pockets ■ Specifications ・Weight: 890g ・Capacity: 14+3L ・Size: H46 x W26 x D18cm