Trail Rolltop Messenger Bag is a compact commuter bag. A bike attachment transforms it into a ride-friendly pannier bag. Trail Rolltop Messenger Bag is the perfect bag for commutes in the city. Simply fold the rolltop opening to protect essentials from rain. Compress and tighten the bag further using the straps and buckle closures on the sides. This elevated rolltop version is fitted with the 'Hook on System'* from cycle equipment experts BASIL, a patented attachment which transforms it into a ride-friendly pannier bag. When on the move by foot, carry the Trail Rolltop Messenger in the carry handle, on the shoulder or crossbody. Trail Rolltop Messenger Bag is cut from Rains' signature PU fabric, engineered for carrying strength, durability and a smooth feel. *Hook on System Explainer: Unzip the backside pocket to reveal the 'Hook on System'. Simply slide the 2 clip parts over one side of the fitted rear rack on the bicycle. Move the central lever 90 degrees to double secure the bag.