A perfect backpack for your hike! The material of choice for this bag is nylon and it holds 26 litres.
From Amazon
Osprey Europe - Talon 26, Ceramic Blue, L/XL
The product is available from £94.88 at international stores.
Trekkinn
Osprey Talon 26l Backpack Blue L-XL
Sigma Sports
Osprey Talon 26 Backpack