The mouse works perfectly. Upon connecting, the computer recognized it as two separate mice and allows for simultaneous connections. One connection uses Bluetooth 3, the other uses Bluetooth 4. A button on the bottom lets you switch between which computer to use. Pressing this button illuminates a green LED to indicate the selected connection. The first connection is furthest forward. Pressing the button again activates the second connection, and so on. The mouse also includes a small USB connector, enabling the connection to a third and fourth computer if needed. I also use one keyboard with two computers. Delivery took 4 days in China, including the flight. Customs clearance in my country took a week. However, the mouse arrived at my home within 10 days. Great! Happy :)