100% brand new and high quality. Tracking systems: Optical. Ergonomically designed, long-term use without fatigue. Built-weight iron, feel comfortable, mobile and stability. Compatible with Windows XP, Vista, Windows 7, ME, 2000 and Mac OS...or latest. Oerview: This is a new 5500 DPI 7 Button USB Wired Gaming Mouse, with multifunction, such as, high quality wire material: the red and black braided wire sync equipped the strong defense magnet ring which can strong anti-interference, Ultra-strong and durable, Gaming adjustment, Comfortable palm feeling, Relieve tired, etc. Plug and Play. Features: 1. Intelligent connectivity, no need to code, plug & play 2. Buttons: 7 buttons with scroll wheel 3. Tracking systems: Optical 4. The Max DPI:5500DPI 5. Ultra-precise Scroll Wheel 6. Optical technology works on most surfaces 7. Ergonomically designed, long-term use without fatigue 8. Switch Life: 5 million cycle 9. Adjustable DPI Switch: 1000DPI / 1600DPI / 2400DPI / 3200DPI /5500DPI Specifications: 1. Size: 130(L) x 105(W) x 45(H) mm 2. Package weight:5.5 oz 3. The length of the USB cable: 1.5m Explanation For The Button 1. DPI button to change LED colors Press the "DPI" button to change the color. Then the LED flashes rapidly 7 times and then remains constant color. (Was not only a specific color) 2. Fire button (on the top left) This key is the same as double clicking the left button. (Two clicks for left button) Compatible Systems: Compatible with Windows 7, Windows 8, Windows XP, Vista, ME, 2000, Mac OS and other OS What is included: 1 X 5500DPI Gaming Mouse.