Just a quick explanation...The older Neotel modems that did not require a SIM (or RUIM in CDMA speak) card, is Neotel pre-configured devices - probably using MAC authentication. The latest CDMA devices does use a SIM, thus you can use any device that is CDMA EVDO RevA compatible. Obviously, the router/PC etc that you connect the USB stick to must have the drivers to support this modems. The Neotel USB "stick" has the drivers/software built-in, and will install them as soon as you connect it to a PC.