Trespass Rucpac Packaway Rucksack/Backpack (15 Liters) (One Size) (Assorted) Trespass Rucpac Packaway Rucksack is a 15 Liter Day pack that packs to a small pocket size. Handy wherever you are. Lightweight polyester double ripstop fabric. Two zipped side pockets. Water repellent finish.