Product Description

HDMI over 50m CAT6 Extender Set

  • Extends 4K 18Gbps signals up to 164ft / 50m. 1080p up to 230ft / 70m

  • Supports 4K HDMI signals up to 18Gbps with HDR, HDCP 2.2, and surround audio up to Dolby® / DTS-HD 5.1

  • Kit includes a transmitter, receiver, power supply, IR emitter, and IR sensor

  • Only requires a power supply on one unit


KD-X444SP is a 4K/UHD 18Gbps, HDCP2.2 compliant HDMI over CAT5e/6 Transmitter plus Receiver set for reliable extension of digital video signals between source and displays.

Full Buffer Technology for Enhanced Reliability

Key Digital’s HDMI extenders, including the KD-X444SP, feature Full Buffer Technology. This technology ensures smooth and efficient HDMI handshakes between devices, preventing compatibility issues.

KD-X444SP offers 16 different EDID handshake options, including auto-EDID. These options guarantee the perfect handshake between your source and display, ensuring optimal video and audio transfer.

Forced Hot Plug Detection

The forced hot plug detection feature helps prevent common HDMI connection issues. It ensures that your HDMI source knows when to output audio and video to the connected display.

This functionality remains reliable even in situations where standard hot-plug detection might fail. This can significantly reduce troubleshooting time and ensure faster sync times.

Support for 4K at 60Hz and HDR

The KD-X444SP HDMI extender over CAT6 supports 4K video at up to 60 frames per second with HDR and up to 4:4:4 chroma sub-sampling.

12-bit deep color support enables HDR video at 60, 30, or 24 frames per second.

Of course, 1080p and lower resolutions may also be extended with additional distance support of up to 230 feet (70 meters).

IR and RS-232 Control

For AV professionals, the KD-X444SP HDMI extender 4K is suitable for advanced control applications. Thanks to convenient control connectivity including a 3.5mm IR control port and RS-232 via a Phoenix connector.

Shelf Mount Solution (KD-SMS16)

For clean installations, mount KD-X444SP on the KD-SMS16 (sold separately) Shelf Mount Solution.

The KD-SMS16 is compatible with various Key Digital products for ease in organizing your AV setup.

Technical Specifications


  • Single CAT5e/6 UTP/STP Extension: Fully automatic equalization, and amplification depending on cabling length

  • 4K Resolution Support: 4096×2160 or 3840×2160 24/25/30/60hz at 4:4:4 (signals up to 18Gbps bandwidth)

  • Flexible Power over CAT (PoC): Only one power connection needed. Tx may power Rx, or Rx may power Tx

  • Low Profile: Super slim chassis design

  • Signal Extension: 4K/UHD (18G), 4K 10G up to 164ft / 50m. 1080p and lower up to 230ft / 70m

  • HDMI Pass-Thru Port (New Q3, 2024): For connecting local monitor, AV surround receiver, and more.

  • IR Sensor: Sensor powering via +5V on IR In ports collects line-of-sight IR from remote(s) without external IR connecting block

  • Up/Down IR: Two channels of IR enable control to/from devices or control systems connected to Tx and Rx units

  • RS-232: Bi-Directional control to/from Tx and Rx unit on Phoenix connector

  • Surround Audio Support: HDMI Pass-Thru supports Dolby®, Dolby® TrueHD, DTS™ and DTS-HD™ (formats up to 7.1); CAT6 Output supports Dolby®, DTS™ (formats up to 5.1/6.1)


  • HDR (High Dynamic Range): More life-like images through a greater range of luminance

  • HDCP 2.2: Compliancy up to HDCP 2.x and backward compliant

  • Visually Lossless Compression: 18G enabling technology applied to all video formats exceeding 10.2Gbps to accommodate transmission channel

  • 10G Pass-thru: Mode enables uncompressed 10.2Gbps signal extension.

  • Deep Color Support: Up to UHD/4K 30Hz 4:4:4/12 bits or 60Hz 4:4:4/8 bit -Full Buffer Technology: Key Digital’s proprietary suite of EDID, HDCP, TMDS, and HPD management to overcome Pro AV installation obstacles.

  • EDID Management: Internal library with 14 internal EDID handshakes including 4K with HDR in addition to native EDID data copied from CAT5e/6 or HDMI pass-thru outputs

  • HDCP Authentication: HDCP sources are authenticated by the HDCP key on transmit unit, for one-to-one topology

  • Hot Plug Detection Control: Enables integrator to choose if the active signal voltage is forced to the connected display/output device

  • TMDS Re-Clocking: Re-generation of TMDS (AV signal) channel data at Transmit unit for brand-new AV signal