Small Size for easy storage, but Large Capacity for mass stuff Product Dimensions 40L: 17.94" x 10.53" x 11.31" 46*27*29cm 50L: 19.89" x 10.53" x 11.7" 51*27*30cm 60L: 22.23" x 11.31" x 12.09" 57*29*31cm Is a knapsack or a luggage suitable for outdoor activities? We doubt it. But what about a lightweight and foldable duffel bag, which is made of durable and water resistant ripstop fabric? It must be a great helper for you and your family on the vacation! Unlike the thick and solid handbag and backpack, this one can be easily bended and the edge can be pressed easily but still equipped with durable laminate material. Just few steps the bag will be fold down neatly into the carry pouch and stay in place. What?s more, this bulky bag itself contain the spacious space for around in-flight, or to be transported up a mountain, definitely being an ideal company with 3 choice: 40?60 liter volume. What are you waiting for? Come and get your burly duffel bag right now!