Found this thread while looking for a similar usb charger - wanted 4 usb outlets with 2.1 amps and needed 50/60hz and 120-240V for European travel. I did find a charger which meets the OP's requirements on amazon; the Scosche QUSBH4 reVIVE IV - 4-Port Usb charger. According to Scoshe's websitet it is a true 4x 1amp each port charger with 50hz/60hz and 120-240v compatibility. Now I'm debating on ordering it at a pricey ~25 versus two of the ~15 2x 2.1 amp per outlet chargers previously mentioned in the thread since it would be approximately the same price, but with redundancy and potentially more versatility with two units.