My husband & I decided to purchase a box (contains 2) of these Ziplock Big Bags for our last vacation. We thought they would be good for storing a bunch of smaller things we didn't want in a suitcase, but didn't want floating around the car either.
The box we purchased came with 2 different size bags. One bag was an XL size which holds about 37 liters. The other was an XXL bag which holds about 75 liters. This didn't mean much at the time we purchase the bags, but after doing our packing, it meant a lot more.
In the XXL bag, we were able to stuff both our pillows and a small blanket and with both of us working to get the air out, we were able to get it fairly flat. In the XL bag, we were able to put all our jackets and rain gear for the trip that we wanted to be able to see and get to quickly.
Overall they worked great and were easy to used and for the price they were a great bargain!