We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Pair of compact aluminium boxes with HDMI and RJ45 ports, plus power adapter and mounting brackets

STARTECH

STARTECH ST121HDBT20L HDMI over CAT6 extender 100m 4K60Hz

SKU CH-0MYC-BXYZ3 MPN ST121HDBT20L

Extends HDMI over a single CAT5e or CAT6 cable with 4K60Hz up to 70m and 1080p60 up to 100m, plus 7.1 audio and power over cable

  • Power draw18 W
  • HousingAluminum
  • Supported resolutions3840 × 2160 (4K) @ 60 Hz 2560 × 1600 1920 × 1200 @ 60 Hz 192
  • Sound7.1 Surround Sound
  • HDMI portsLocal Unit: 1 x HDMI (19-pin) Female Input Remote Unit: 1 x
  • Connection typeLocal Unit: 1 x RJ-45 Female Output Remote Unit: 1 x RJ-45 F
  • 4K60Hz UHD video up to 70m over single CAT5e cable
  • 1080p60 signal reaches 100m using existing network cabling
  • Power over cable removes need for separate receiver supply
  • Aluminium housing with mounting brackets enables tidy professional installs
  • 1 surround sound passes through with IR control included

Extender for 4K60 HDMI over CAT6

The StarTech ST121HDBT20L transmits HDMI signals up to 100 metres over a single CAT5e or CAT6 cable. It supports 3840x2160 at 60 Hz to 70 metres and 1080p at 60 Hz to the full 100 metres. The aluminium transmitter and receiver each measure 1.00 by 3.00 by 4.00 inches and weigh 0.24 lb. Installers and AV integrators use it to bridge projectors, displays or matrices across rooms or floors.

Power-over-cable kit with IR and mounts

A universal AC adapter powers the local unit; the remote unit draws power over the same CAT cable, so no outlet is needed at the display. The box includes an IR blaster, IR receiver, two mounting brackets and eight rubber feet for fixed or surface mounting. A status LED on each unit confirms link and signal integrity. Setup requires no software or configuration.

70-metre 4K60 headroom, 100-metre 1080p limit

At 70 metres the extender carries full 4096x2160 60 Hz with 7.1 surround audio. Beyond that distance it falls back to 1920x1080 60 Hz up to the 100-metre maximum. It does not support HDR metadata, HDCP 2.3 or resolutions above 4K60. Buyers needing 4K60 past 70 metres or 8K transport should consider fibre-based solutions.

How it compares

Measured against everything we stock in A/V Extenders & USB Hubs, at today’s prices. Recalculated every night.

Price $375.99
Pricier than about 87% of the 239 comparable items (median $132.99).

Specifications

Product
Brand nameStarTech.com
Model nameST121HDBT20L
Display
Supported resolutions3840 × 2160 (4K) @ 60 Hz
2560 × 1600
1920 × 1200 @ 60 Hz
1920 × 1080 (1080p)
1280 × 720 (720p)
Audio & video
Sound7.1 Surround Sound
Connectivity
Connection typeLocal Unit: 1 x RJ-45 Female Output
Remote Unit: 1 x RJ-45 Female Input
Ports & slots
HDMI portsLocal Unit: 1 x HDMI (19-pin) Female Input
Remote Unit: 1 x HDMI (19-pin) Female Output
Power
Power draw18 W
Size & build
Product dimensions1 in × 3 in × 4 in
Product weight0.24 lb (0.11 kg)
Shipping weight0.23 kg
Package size280 × 206 × 62 mm
In the box
Included items1 x HDMI over CAT6 transmitter
1 x HDMI over CAT6 receiver
1 x universal power adapter (NA/JP, EU, UK, ANZ)
1 x IR blaster
1 x IR receiver
2 x mounting brackets
8 x rubber feet
1 x quick-start guide
More details
HousingAluminum
Indicator light1 x status LED (local)
1 x status LED (remote)

Questions about this item

Will the power adapter need replacing after long-term use?

The included universal AC adapter supplies 18 V DC at 1 A and is rated for 100–240 V AC input, so it can be swapped with any matching 18 V DC 1 A supply if it ever fails.

At what distance does the 4K 60 Hz signal drop to 1080p?

4K 60 Hz is supported up to 70 m (230 ft); beyond that, up to 100 m (330 ft), the maximum resolution falls to 1080p 60 Hz.

How much heat or noise does the extender produce when running continuously?

The aluminium-housed units draw 18 W total with no fans, so they run silently and generate only modest warmth during all-day operation.

More in A/V Extenders & USB Hubs

Similar items