These packing cubes gently compresses clothes without wrinkling your clothing. I was able to use a carryon to travel on vacation for a week using these. These are a nice quality and the zippers run smoothly. These also organize your bag so that one night stay over by the Airport doesn't wreck your whole back searching for that one item that slipped to the bottom of the bag. I did find when compressing the bag with clothes in the bag, sticking your finger between the fabric of the bag and the zipper when closing so the fabric of the bag does not get stuck in the zipper. Though the plastic vacuum or roll compression backs do a better job at compressing your clothes, the benefit of not worrying that the bag gets a pinhole in it to render it useless is well worth it. This bag is a lot more rugged. Also, being that this gently compresses the clothes, the bag is more forgiving than the plastic compression vacuum bags when you have a bad fold. I use the small bag daily for medications, toothbrush, etc that I keep in my work bag along side my laptop.