WAXED DUCK CANVAS WITH RED WING LEATHER GR1, the best rucksack ever built, meets time proven heavy canvas materials and construction. Heritage means it’s proven by our grandfathers, and our grandfather’s grandfathers. And that it will last the test of time for those generations who come after us. For materials, we chose the strongest possible duck canvas with a waxing process proven over the last 170 years, giving the Heritage a retro canvas rucksack look with the durability you'd expect from a GR1.