The Fanvil X4U is a sophisticated gigabit SIP enterprise desktop phone designed to meet the needs of modern business environments. Featuring a 2.8-inch main color LCD display with a resolution of 320x240, the X4U offers clear and detailed visual access to call information and settings. Additionally, it includes two secondary 2.4-inch color LCDs, which are used for programmable keys, each with dual-color LEDs for easy line management and status indication.

The phone is equipped with 12 programmable line keys, 6 soft keys, 4 navigation keys (up, down, left, right), and 4 dedicated function keys (such as call, end, and menu), ensuring intuitive operation and quick access to essential functions. The X4U supports high-definition (HD) audio with advanced codecs including G.711a/μ, G.729, G.722, G.723, and G.726, providing crystal-clear sound quality. Echo cancellation and noise reduction further enhance the audio experience.

The full-duplex speakerphone enables hands-free communication, while the phone supports both RJ-9 and an optional 3.5mm headset connection, offering flexibility in audio options. Network connectivity is robust with dual 10/100/1000 Mbps Ethernet ports, and Power over Ethernet (PoE) support simplifies installation. An optional external power adapter (5V DC, 2A) is available for additional power options.

The X4U supports SIP v2 (RFC 3261) and accommodates up to 4 SIP accounts, making it suitable for diverse business communication needs. It includes a comprehensive set of call handling features such as call transfer, call forwarding, call hold, 3-way conference calling, call waiting, and caller ID.

Security is reinforced with support for TLS, SRTP, HTTPS, and 802.1x network authentication. Firmware updates can be managed remotely via TFTP, FTP, or HTTP, ensuring the phone remains up-to-date with the latest features and security patches.

The Fanvil X4U is designed for easy desktop use with an included stand and can also be wall-mounted with an optional bracket. With its sleek black design, the phone seamlessly integrates into any professional setting, combining functionality with a modern appearance.