Features:2.4G wireless transmission technology provides reliable connection within a range of 10m, allows you to say goodbye to the wired shackles and operate more freely.Ergonomic design, fits the hand, provides comfortable feel, effectively reduces hand fatigue.Humanized silent design, creates a quiet and comfortable environment whether you are in quiet office or studying late at night in the library.Three adjustable DPI provide sensitive response and smooth operation, can position accurately in fast moving.Slim design, lightweight and portable, you can easily put it in a bag or pocket, more convenient to use.No driver requied, plug and play.Built-in 500mAh rechargeable battery, adopt Low power and energy saving technology, no need to charge the battery repeatedly.Specification:Name: Wireless mouseModel: M40Color: BlackMaterial: ABSNumber of keys: 4Type: 2.4G WirelessTransmission distance: Up to 10mDPI: 800-1200-1600DPIBattery Capacity: 500mAh(rechargeable lithium battery)Item size: 11.3 * 5.8 * 2.6cm /4.45 * 2.28 * 1.02in(L * W * H)Item weight: Approx. 79g /2.79ozPacking list:1 * Mouse  1 * USB cable