The UM 150 also includes a micro SD card slot, which supports cards up to 4Gb in size. It weighs just 1.6 ounces, and plugs into a USB port. Software for Windows and MacOS is included. Verizon's EVDO Rev A network supports download speeds of 600 to 1400kbps and upload speeds of 500 to 800 kbps. A set of LEDs on the body of the device show the current signal strength, and when data is being sent or received. An external antenna connection allows for the use of better external antennas if required.