The Microsoft Natural Ergonomic Keyboard 4000 (v1.0) is a popular keyboard designed to reduce strain on the hands and wrists by offering an ergonomic, split keyboard layout. Here are its key specs: Layout: Ergonomic, with a split design for better wrist posture. Keys: 104 keys (including a dedicated number pad). Key Switch Type: Membrane key switches. Connectivity: Wired USB connection. Dimensions: Approx. 19.25 x 10.75 x 2.25 inches (L x W x H). Weight: About 2.3 lbs (1.04 kg). Tilt: Adjustable to different angles to customize the typing experience. Key Features: Split keyboard layout with a separate numeric keypad. Contoured design with a cushioned palm rest. Customizable hotkeys. Multimedia controls (e.g., volume, play/pause). Zoom slider for quick zoom functions. Windows and Application keys for productivity shortcuts. Compatibility: Windows XP, Vista, 7, 8, 10, and later versions. This model is known for its comfort-oriented design, aimed at improving ergonomics for long typing sessions.