2.4GHz WIRELESS CONNECTION: Utilizes advanced 2.4GHz wireless technology, plug and play, no additional drivers required. Stable signal transmission, working range up to 33ft. USB receiver is inserted into the battery compartment of the keyboard. ERGONOMIC DESIGN: Integrated ergonomic tilt provides comfort that helps reduce strain. The good spring actions and comfortable key sizes respond quickly, improving your work efficiency, great for those who work with spreadsheets, accounting files, or financial applications. ANTISLIP AND PORTABLE DESIGN: There are four anti-slip mats on the back of the number keypad to prevent it from sliding around your desk when in use. This stable number pad is easy to take with you, so you can work safely and quickly anywhere and everywhere. POWER SAVING: It will automatically turn off when not in use for 10 minutes, effectively extending battery life. UNIVERSAL COMPATIBILITY: Lefon wireless number pad works with PCs, laptops, and desktop computers that have Windows 2000, XP, Vista, 7, 8, 10 systems. The wireless 18-key numeric keypad is not fully compatible with Mac OS. Specification Operating Frequency: 2.4G technology Structure: Solid Fastening buckle bit bag material: ABS Power supply: 1 * AAA battery (not included) Effective distance: about 328FT (10M) 2 Options For Your Choice 1.Keyboard Mouse Combo Set Package Content: 1 x 18 Keys Wireless Digital Keyboard 1 x Wireless Mouse 1 x 2.4G Wireless USB Receiver 2.Keyboard Package Content: 1 x 18 Keys Wireless Digital Keypad 1 x 2.4G Wireless USB Receiver