Do not buy this product. The idea of the product is a good one but the quality is very poor. The bag is so cheap it is so hard to get the zipper to open. One of the cups came with the rubber ring to seal the lid to the cup bent and looked discolored it was yellow not like the other cup. It does not seal right. Don't even know if it is worth sending back because if they say there is nothing wrong the shipping will cost more than the product is worth. I am so unhappy with this purchase will not order this kind of product online again you really need to see the quality before buying.