No, you don't need to get the vacuum bags. You can buy the similar bags that you just roll the air out of. They are actually great for things like towels and jackets. In any event, you just put your towel in the bag, roll it and the air gets pushed out, the whole package squishes sort of flattish and as long as you don't pooch the seal, it works like a hot damn. On the other hand, they aren't so good with the rest of your clothes if you were thinking that you'd get there without any wrinkles in them (as the advert claims). For me, I use them for my fleecy, shorts and a couple of bathing suits. Bags still weigh heavy but I can fit what I like into a smaller carry on and into my checked bags.
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