I purchased 2 Universal Travel AC Wall Adapters, with USB Charger, for my daughters' trips to Europe.  Both units worked for about 1 day or less, when they stopped working during use.  They used them with dual voltage camera battery chargers.  I had also given them straight plug adapters.  Thank God that I did!  The straight plug adapters, which I bought in 1999, still worked, and lasted them the rest of the trip.  Good thing I also included USB charger units.  So they could not charge 2 items at the same time, since the new wall adapters broke, but they got their gadgets charged with the other plugs.