This bag is the right size to hold at least seven to ten days worth of either ladies underwear or short socks.  I bought two and used one for my the top undies and the other for socks.  These cubes are well worth it for a few reasons: (1) makes living out of a suitcase easier since you're not digging through other clothing to get to these, (2) X-Ray friendly - which makes it less likely your case will be opened by TSA, (3) if the TSA does open your case, assuming you've used different cubes for all your clothing, it's unlikely that your items will be damaged by being pinched in the suitcase seams.