100% double waxed canvas. The fabric is quite thick and, because it is waxed, it is extremely water resistant. Using as bushcraft backpack, camping backpack, outdoor backpack, hiking backpack, daypack, trekking backpack. Sizes: 30 – 35 – 40 – 45 – 50 – 60 – 70 – 80 liters. All features is same only flap and bottom type is optional- for other request you can reach me. We can personalize depending on your request. This item is made of metal buckles, d rings, waxed canvas, genuine leather, brass, canvas, vegetal leather, ring, leather and nikel.