Zipper closure EASY TO USE! Compression packing cubes help you with packaging your clothes for upcoming trips by compressing the air out of them. These are not your typical vacuum bags-these expandable cubes use a two zipper system to help eliminate the extra bulk when packing your luggage. The zippers literally compress your clothes together and eliminate wasted space. Skip the extra fees of a checked bag- eliminate the bulk and use a carryon instead! LUGGAGE ORGANIZER! Compression packing bags are a packing essential for travel-especially useful as a backpack, luggage and suitcase organizer. Keep different outfits in separate compression cubes and always be ready for whats next! Easily pack away clothing like raincoats/heavier jackets that are not used as often. Use empty cubes to pack dirty laundry in and keep your suitcase or backpack organized.