Named after the Italian word for Brick, the Silca Mattone is a water-resistant, ultra-compact seat bag that attaches to the rails using a super secure BOA® Closure System. Unique zipper design allows it to be accessed while on the bike, or to open like a book when removed from the bike for easy access. The Mattone will easily carry a spare tube, CO2, Multi-Tool, and some cash in a discrete, water-resistant package. Internal divider holds ID, credit card or cash while also protecting your tube from your multi-tool! Specification Exterior - Sleek black finish with reflective graphics. Interior - Hi-contrast red material with separate ID, credit card or money flap. Interior Volume - Holds one inner tube, one CO2 cartridge, one tire lever (all of these components are sold separately and are not included). BOA® Closure System with open guide release on Hypalon retaining strap. YKK Aquaguard® zipper. Outside Dimensions: 13cm x 8.5cm x 5.5cm. Volume: Approximately .61 L. Strap Measurements: 27cm x 4.5cm.