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 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 Win7/Win8/Win10. Package List: 1 x 2.4G Wireless Numeric Keyboard1 x Receiver1 x User Manual Note: Manual measurement, there is an error of ±0.5mm, please refer to the actual product.