Whitmor's improved Spacemaker vacuum bags have a durable multi-layer construction for maximum use and reuse. The zipper slider has been improved to slider prevent it from sliding off when sealing the bag. A patented no-cap valve prevents air from seeping in over time. These storage bags create an airtight barrier to protect against odor, mold, mildew, insects, and moths. This set includes 1 travel bag 27.6 x 19.7 inches, 2 Medium 18 x 24 inches, 2 large bags 24 x 36 inches and 1 extra-large 30 x 42 inches. Whitmor is a 4th generation family-owned and operated business. Since 1946, Whitmor has been dedicated to bringing organization home by creating products that simplify everyday life. Ensuring that those products are built with integrity, value, and innovation is our commitment to you. And our promise is that we will always be here for you should you ever need us as we stand behind our product 100%. Whitmor customer service is available in English and Spanish Monday through Friday from 8 am - 4:30 pm CST. Call us and we will gladly assist you in your language. You may contact Whitmor toll-free at 1-888-944-8667 or via email at help@whitmor.com.