With its lightweight materials and reversible, double-duty design, the Eco-Arete 18 is one of the most versatile packs we make. This bag gives you room for snacks, layers, essentials, and 1.5 liters of water. It's lightweight materials and packable design also make it an excellent travel bag that won't add bulk to your luggage. We updated this version of the Arete with additional pockets to keep your gear organized, along with a removable sternum strap. This bag is made with waterless dyed lining, recycled poly airmesh harness, recycled poly pocket mesh. The reservoir is not included.