Features: 1.Stable wireless connection function, effective control range up to 10meter. 2.The numeric keyboard uses the mute button to create a quiet typing environment for you. 3.Low power consumption, strong battery life up to 12 months, long battery life. 4.2.4GHz wireless connection, 18-key design, with backspace key, you can easily correct the text. 5.System requirements for Windows XP/Win7/Win8/Win10/IOS, with strong adaptability. specification:Item Type: AJAZZ Wireless Numeric Keyboard Product Model: AK18 Product Name: 2.4G wireless numeric keyboard Product Size: Approx. 89 x 129 x 27.5mm / 3.5 x 5.1 x 1.1in Weight: Approx. 100 g / 3.5 oz (5 g / 0.2 oz)(including counterweight) Battery Type: 1 x AAA battery (not included) Number of Keys: 18key Connection Method: RF 2.4GHz System Requirements: For Windows XP/Win7/Win8/Win10/IOS PackageList: 1 x 2.4G Wireless Numeric Keyboard 1 x Receiver 1 x User Manual NoteManual measurement, there is an error of 0.5mm, please refer to the actual product.