Bluetooth technology provides stable wireless connection, the external 29-keys keypad extends your existing keyboard, operating distance of 10mCalculator function, with the large 12-digit LCD display for much precise countingBuilt-in a lithium rechargeable battery, easily recharged through the USB cableErgonomic design, reduce the stress when typing, excellent for spreadsheets worker, accounting staff and financial officersWide compaility, suitable for MacBook, for Windows, etc Specification: Wireless technology: Bluetooth 4.0Size: 146.4*130*11mmWeight: 165gNumber of keys: 29 keysButton life: 12 million timesDisplay: 12-digit display Package included: 1 x Keypad 1 x Charging Cable 1 x English and Chinese User Manual Other things not included