Feature: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 Win7/Win8/Win10, with strong adaptability.Specification:Item Type: Wireless Numeric KeyboardProduct Model: AK18Product Name: 2.4G wireless numeric keyboardProduct Size: Approx. 89 x 129 x 27.5mm / 3.5 x 5.1 x 1.1inWeight: Approx. 100 g / 3.5 oz (5 g / 0.2 oz)(including counterweight)Battery Type: 1 x AAA battery (not included)Number of Keys: 18keyConnection Method: RF 2.4GHzSystem Requirements: For Win7/Win8/Win10.Package List:1 x 2.4G Wireless Numeric Keyboard1 x Receiver1 x User ManualNote:Manual measurement, there is an error of 0.5mm, please refer to the actual product.