Nomatic Travel Bag 40L – Best Carry-On Backpack for 3–7 Day 。?Large Capacity & Expandable:20 X 13.6 X 6+2 inch. This travel backpacks flight approved has 1 main compartment with elastic retention straps on the inside and a large mesh zipper pocket that can keep 3-4 day clothes (depends on your packing way) This backpack for men can become bigger or smaller via 2 straps on either side and a zipper compression to meet your different packing capacity requirement so you can easily keep packing cubes, clothes and shoes into this weekender backpack ?Convenient & Easy to Organize:This luggage bag has 2 front compartments with small pockets for organizing and quick access to your small items like phone. It carries like a pack yet be packed like a suitcase so everything is organized and laid out and not stuffed down in a bottomless abyss like traditional backpack. It has a strap on the back of the bag to secure it to the handle of roller bag so that you don\'t have to wear it on your back until you are actually boarding the plane ?Great Quality & Versatile:This backpack for travel is made of sturdy water resistant polyester with lockable zipper heads. It is comfortable to wear for the really thick padding on the shoulder straps and back, and it can fit nicely on your back and distribute the weights somewhat evenly. ?Additional Toiletry Bag:Dimension:9.5*5*4.5inches. This airplane backpack comes with a toiletry bag providing extra storage with ease whether you are on a short trip or traveling for business.