GIVI Corium Rucksack/Seat Bag 18 LGIVI Corium Rucksack Seat Bag 18 L Rucksack which can also be used as a seat bag, 18 litre. With its classic design, it is particularly suitable for retro style bikes or cafe racers. Materials: High tenacity 1200D W R coarse polyester Dark brown and black PU. As standard: Retractable shoulder straps to allow use as a seat bag 4 straps for fastening to saddle Waterproof roll top closure system Removable waterproof inner bag with IPX5 impermeability