Packing cubes are ingeniously simple in design, yet offer endless possibilities for organization and efficiency when traveling. These useful items are tiny soft suitcases that fit inside your luggage and, when used properly, can keep your apparel and accessories well ordered while conserving space. But the best ones have a few features that set them apart from the lesser sets.

Packing cubes need to be manufactured using durable material. Vinyl might seem like a good choice when considering price, but it won’t hold up like polyester or insulated nylon. Be careful when purchasing cubes with external features like mesh, which could snag, and always be sure the zipper is of highest quality.

If you’d like to learn a few more tricks about packing, storing, and choosing the right packing cubes for your specific needs, keep reading. If you understand how these rectangular wonders work and are ready to buy, consider one of our favorite options.