A backpack such as this one can be very useful for a number of things. This hiking backpack is made exclusively from synthetic material and it holds 10 litres.
From Amazon
Salomon Trailblazer 10 Unisex Hiking Backpack, 10L Versatility, Easy to Use, and Comfort and Lightweight, Black
RunningXpert
Salomon Trailblazer 10 ONESIZE