Please Note: This product is an add on and does not include the base bag. Only one side pouch can be used on the bag at a time. These side pouches attach with sturdy Velcro to the side of the messenger bag to allow for peripheral storage. Small - Designed for a compact digital camera, mp3 player, or cell-phone. Includes a headphone port to simplify your listening experience on the move! Can also be used as a standalone camera case. Large Perfect fit for bulkier items like chargers, cables, art supplies, even a 16 oz. water bottle!