ERGONOMIC AND POWER SAVING: pads on back provide optimum comfort and securely keep the bluetooth numpad in place. It will auto power-saving mode when not in use for 15 minutes, Press any key can awake up the keypad.Power Supply by 1* AAA Battery ( not included )SIMPLE SETUP: Its easy to get startedou just plug the receiver into a USB port and start crunching numbers right away.The USB Receiver is inserted in the battery compartment of the keyboard no drivers required. Keys are easy and silent to press, greatly speed up your productivity QUIET SOFT TOUCH: Integrated ergonomic tilt provides added comfort which helps reduce strain, great for those working on spreadsheets, accounting files or financial applications.USER FRIENDLY: Battery indicator light lets you know when the keypad's AAA battery is running low. Conveniently located direction control keys can be used as joystick control, allowing you to feel the thrill of playing game using a wireless device