SLIM ALUMINUM DESIGN: Bluetooth number pad is constructed of solid and premium aluminum materials for long-lasting use, the ergonomic tilt for comfortable typing and good look, slim style appearance ( Only 0.46lb, 5.7*4.4*0.47 inch ), perfectly matches your Macbook, MacBook Air / Pro, iMac, PC, surface pro, laptop or desktop as the side external numeric keypad. BLUETOOTH 3.0 CONNECTION: Bluetooth 3.0 technology provides a cable-free & clutter-free connection, the external 34-keys full keypad extends your existing keyboard, operating distance 10m. NOTE: For Laptop Desktop PC without Bluetooth function, you need to use third-party Bluetooth adapter (not included) before use HIGH-CAPACITY RECHARGEABLE BATTERY: Built-in 160mAh lithium rechargeable battery. The Bluetooth numeric keypad is easily recharged through the included USB cable, no need to change the battery and user- friendly. The Bluetooth wireless keypad also has the auto sleep function, lower power consumption,