Topeak MTX Trunk Bag DX. Designed for the MTX Rear seat post rack. Securely slides and locks into place when used with a MTX seat post rack. May be used with other rear racks, however it really is designed for the MTX rack. The padded, insulated walls of this bag make it a great camera case or cooler (Topeak boasts that it can carry eight 16-oz cans!). The already-large main compartment expands for that extra cargo. Additional features include: * High-quality 2,520-denier pack fabric; coated with Dupont Teflon fabric protector. * Extra-thick and rigid foam sides on top and bottom * 3M reflective strip for safety * Built-in carrying handle * Detachable shoulder strap * Compatible with Quick Clip mount for QR Beam Rack MTX * Weight: 3 lb 1 oz * Dimensions: 32 x 16.5 x 23-33 cm (expandable) * Volume: 800 cu. in. (expandable). * Pack Fabric: 2520-denier & 840-denier nylon fabric* Free shipping on all orders over $100.00! AL's one-liner (Don't learn the tricks of the trade, learn the trade.)