Product Features: ◆Calculator: The wireless usb numeric keypad can use a calculator or the keyboard mode. The switch (PC/CAL) between them. ◆Connect: When calculator and computer connection, install batteries, you can click "connect" button to connect to the computer, and then you can press the "send" key calculation results will be sent to the computer. ◆Solar: And solar keyboard, you don't need the battery, when you use it as a calculator, if you use it as a numeric keypad, you need to install 2 aaa batteries (not including battery) ◆comfortable: Big, full size, soft concave button to improve efficiency. Plug and play. Compact, convenient wireless keyboard backspace ◆Method of use: USB device inserted an empty USB port, wait about 10 seconds, and set to work, no drivers to install, no software, easy to control the Support the numeric keypad on the keyboard ◆System requirements: Windows XP or Vista / 7/8/10. ◆note: Mac OS X is not compatible with the keyboard. Product Specifications: Material: ABS Color: Black Operating frequency: 2.4G technology Interface: Wireless usb 2.0 interfaces Receiver: USB Receiver,25 feet from the computer. Key Mechanical working life : The keycaps life of more than 5 million times System Requirements: Compatible with Windows XP / 7 / 8 Environment Temperature: Operating 5 ℃ ~ 50 ℃, Storage: - 20 ℃ ~ 65 ℃ Relative Humidity: Operation 10% ~ 85% RH 25 ℃，Storage: 5% ~ 95% RH 25 ℃ Solar Panel,no need batteries while use it as a calculator. 10 digits and a built-in pocket calculator Smooth shift from calculator to numeric keypad Product Dimension:6.10x0.59x3.94in Package list: 1*mini calculator numeric pad 1 *USB Receiver 1*use manual