①. SLIM ALUMINUM DESIGN: The Bluetooth numeric keypad is made of sturdy and premium aluminum materials for durability, ergonomic tilt for comfortable typing and beautiful appearance, slim style (only 0.46 lbs, 5.7 x 4.4 x 0.47 inches). ②. BLUETOOTH 3.0 CONNECTIVITY: Bluetooth 3.0 technology provides wireless, cable - free connection; the wireless external 34 - key keyboard extends the existing keyboard up to 10m operating distance. 【NOTE: For desktop laptops without Bluetooth function, you need to use a third - party Bluetooth adapter (not included) before use. ③. LARGE CAPACITY RECHARGEABLE BATTERY: Built - in 160mAh rechargeable lithium battery. The Bluetooth numeric keypad is easily charged via the included USB cable, no need to replace the battery and convenient to use. The wireless Bluetooth keyboard also has an auto - sleep function, lower power consumption, reflects energy saving and product customization. Press any key to wake up the keyboard in 3... seconds. ④. HIGHLY COMPATIBLE: This wireless Bluetooth numeric keypad keyboard design features a low - profile, quiet hotkeys and scissor switches for comfortable working on your computer or laptop. Compatible with Windows, Android, iMac, MacBook Pro, MacBook Air, MacBook, Surface Pro, laptops, desktops, tablets, etc. 【NOTE: The 10 key is NOT compatible with ChromeBook. The Page Up, Page Down, Search, Screenshot and Ins keys will not work with Mac OS, but other keys and number keys work fine.】