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StarTech HDMI over CAT5 HDBaseT Extender - 4K

Model Number: ST121HDBTE
Web Code: 10622295

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Requires only a single power adapter for both the Transmitter and ReceiverCost-effective HDMI extension through non-proprietary network cablingOptional mounting hardware included for a tidy, professional installation
SAVE $31$296.99
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Requires only a single power adapter for both the Transmitter and ReceiverCost-effective HDMI extension through non-proprietary network cablingOptional mounting hardware included for a tidy, professional installation

The StarTech HDBaseT extender kit, extends HDMI up to 230 feet (70 Meters) over a single CAT5e or CAT6 cable. The extender supports Ultra HD and Full HD resolutions (4K / 1080p) with support for 3D and the accompanying digital audio. For added versatility, both the transmitter and receiver can be powered by the same single power source using Power Over Cable (POC). The versatility of this video extender makes it an ideal solution for digital signage applications in large buildings such as commercial shopping centers, stadiums, schools, and hospitals.

What is HDBaseT?

HDBaseT is a standardized, zero latency, video distribution technology that’s revolutionizing HDMI distribution. HDBaseT uses an advanced method of modulation that enables you to distribute uncompressed HDMI audio and video along with additional signals such as 100BaseT Ethernet, IR, RS-232 serial and power over cable.

Extend more with HDBaseT

The extender offers HDBaseT technology with HDMI and Power in a single extender kit, for complete end-to-end solution. Offering greater versatility than traditional HDMI extenders or HDMI cabling alone HDBaseT is the clear choice for every integrator and system designer. The added benefit of power over cable means you’ll only need one power source at either side of your extension, great for extending video to areas where power outlets may be limited, such as industrial sites.

Astonishing 4K picture quality from an impressive distance

With the A/V industry quickly adopting 4K as the new high-resolution video standard, long range video distribution can be a challenge with standard HDMI cables beginning signal degradation at 30 feet.

With support for 4K you’ll be amazed at how HDBaseT maintains your Ultra HD picture quality, four times the resolution of high-definition 1080p, even at 130 feet away from your video source. Plus, because the extender supports High-Definition 1080p and lower resolutions at 230 feet away, you can comfortably use this extender to make any video source look great.

Simplify your setup

This extender has been specially crafted for a smooth, tidy installation. HDBaseT technology allows for single cable installation, for seamless integration using existing CAT5e or CAT6 infrastructure, avoiding the hassle of running multiple Ethernet cables while, reducing potential failure points. Plus, the added benefit of power over cable means you’ll only need one power source to power both your extender and receiver, great for extending to areas where power outlets may be limited. Mounting hardware is also included for both the extender and receiver for discrete, professional mounting.

The ST121HDBTE is backed by a 2-year StarTech warranty and free lifetime technical support.

Cable Type


End Type #1
End Type #1 Female Or Male
End Type #2
Not Applicable
End Type #2 Female Or Male
End Type #3
Not Applicable


Maximum Resolution
1080p HD
Cable Length (m)
0.1 m


Seller's Warranty - Parts
2 Years
Seller's Warranty - Labour
2 Years
  • HDMI over CAT5e/6 transmitter unitHDMI over CAT5e/6 receiver unituniversal power adapter (NA/EU/UK/AU)mounting bracket kitCat5e cablegrounding wiresinstruction manual

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Rating Breakdown












  • Nice Picture
    Reviewed by EdDyP123 - September 29, 2017

    I often like to show family members videos and pictures of our vacation and the kids from the computer on the TV. We also like to watch a lot of streamed content as well. My TV is not a smart TV so I can't stream content to it from my computer. I often have to copy everything to a USB stick and plug that into my TV. This eliminates that by being able to hook my computer from across the room to my TV as a monitor and watch media content on my TV from my computer without having to move it. Picture is clear without any degradation. The two units are small enough to tuck away out of sight. Did what I needed it to do. I received this product in exchange for an unbiased review.

    Review originally posted on

  • HDMI over network cable that works!
    Reviewed by ScottG416 - January 14, 2017

    I was tasked with having users mirror their laptop on a tv (after the built was complete) without software and I have found the answer. A facility had just finished a renovation and the tv was mounted, power was installed and network drops were in place but no thought had gone into how to utilize the boardroom to its full potential. After much discussion with endusers and management the most cost effective way would be to use an HDMI extender without any software installation required (since most laptops are locked down these days). With cables plugged in (HDMI and CAT5/6) all is left for the user to do is to plug in HDMI to their laptop and we now have the laptop screen on the tv. Another great product from I received this product in exchange for an unbiased review.

    Review originally posted on

  • Does not work on my redeliver
    Reviewed by EnIXmA - January 30, 2016

    Bought this specifically for my 4k TV which is being connected by the latest onkyo receiver... Connected, and everything perfectly fine for 2 days... For some reason it just shows no signal on my TV now... The lights are blue so the connection should work, but it doesn't. Seems like I wasted 300 bucks on this and got no way to run my ht system

    Review originally posted on

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Returns can be made within 14-30 days of receiving your order.

Best Buy for Business Restocking Fees / Return Eligibility
Category Return Period Un-opened Opened/Unused Opened/Used
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Cell Phones 15 Days 0% 10% 10%
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Furniture & Decor, Home Office Furniture 30 Days 0% Must be unassembled Not Returnable
Books, Magazines, and Copyright Materials, Digital Downloads, Intimate Products, Pre-paid Cards, Services, Deliveries & Installations, Food, Vitamins & Supplements, Earrings 30 Days Not Returnable Not Returnable Not Returnable
All other products 30 Days 0% 10% 10%

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Return shipping costs will be paid by the seller for all cases where the product is defective, damaged or incorrect. For other cases (e.g. you changed your mind), you will be responsible for this cost.

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  • Date you recieved your product
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