100% brand new and high quality Features: One-to-many connection: One tiny receiver for up to six Unifying devices. Plug it and leave it, then connect additional mice and keyboards to one computer. Download Unifying software to quickly add all of your devices to one receiver. It's convenient, clutter free, advance 2.4 GHz wireless technology. For easy mobility and exceptional experience, keep a mouse-and-keyboard at work, at home and in your computer bag. They are always ready to use from only one USB port. Compatible with Unifying Mouse or Keyboard: for Anywhere Mouse MX (M905),M325,M585,M510,M705 for Performance Mouse MX (M950) for logitech K400 keyboard for logitech Wireless Solar Keyboard K800 for logitech Number Pad N305 for logitech Wireless Trackball M570. Specifications: Mode: Single channel Device(-14),6 Device(-28) Type: Receiver for logitech Unifying Material: ABS, metal Size: approx. 1.4x1.8x0.6cm / 0.5x0.7x0.2in Quantity: 1pc Note: Single channel Device only supports connect Utility,Unifying does not work. 6 Device only supports connect Unifying. We have two models to choose from: single channel device and 6 channels device. Single channel device can only connect mouse, 6 channels device can connect mouse and keyboard at the same time. Package includes: 1 x Receiver