The HP LaserJet Pro 400 M401dn is a monochrome laser printer designed for small to medium-sized businesses and workgroup environments. Here are some key features and specifications of the HP LaserJet Pro 400 M401dn:

1. Monochrome Printing: This printer is designed for black and white (monochrome) printing only. It’s suitable for text documents, reports, and other black and white materials.
2. Print Speed: It offers fast printing speeds, capable of printing up to 35 pages per minute.
3. Duplex Printing: The “dn” in the name typically signifies duplex printing, meaning it can automatically print on both sides of the page, helping to save paper.
4. Connectivity: It comes with built-in Ethernet networking, making it easy to connect and share the printer within a workgroup or office network.
5. Paper Handling: The printer typically has a standard paper input capacity of around 300 sheets, which can be expanded with additional paper trays. It also includes a manual feed slot for printing on special media or envelopes.
6. Resolution: It offers a high print resolution for sharp text and graphics, usually up to 1200 x 1200 dpi.
7. Mobile Printing: It supports mobile printing options, such as HP ePrint and Apple AirPrint, which allow you to print from mobile devices.
8. Monthly Duty Cycle: The printer’s recommended monthly duty cycle is generally around 750 to 3,000 pages, depending on the specific model and usage.
9. Compatibility: It’s compatible with various operating systems, including Windows and Mac.
10. Security Features: HP LaserJet printers often come with security features to help protect sensitive data, like password-protected printing.
11. Toner Cartridges: It uses black toner cartridges for printing. The specific cartridge model may vary depending on the printer’s version.