RJ21 Cat3 Telco Cables
5 products
RJ21 telco cables (also called Amphenol or "50-pin" cables) are the backbone of traditional voice and multi-line data connectivity. Each cable terminates in a 25-pair RJ21 connector — 50 pins carrying up to 25 individual voice channels or data lines in a single, tidy run — making them the standard choice for PABX/PBX phone systems, voice gateways, LAN cross-connects and MDF/IDF frame wiring.
At DTT UK we build our Cat3 RJ21 cables to BT specification for reliable, interference-free voice-grade performance. We stock a full range of configurations — male and female connectors, straight (180°) and right-angled (90°) hoods, and fan-outs to RJ45, RJ11, Krone or open-end tails — so you can connect telco hardware to patch panels, blocks or handsets without adaptors.
They are a direct match for Cisco VG224, VG310 and VG320 voice gateways and most PABX systems that use the industry-standard Telco/Amphenol interface.
Need a length or configuration you don't see below? Every cable is made to order in our Hungerford workshop — tell us the length, connector type and pin-out and we will build it. Call 01488 685 400 or request a quote. In-stock lines dispatch the same working day.
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RJ21 Cat3 Telco Female - Female
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RJ21 Cat3 Telco Female - Open
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RJ21 Cat3 Telco Male - Female
RJ21 Cat3 Telco Male - Female
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RJ21 Cat3 Telco Male - Male
RJ21 Cat3 Telco Male - Male
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RJ21 Cat3 Telco Male - Open
RJ21 Cat3 Telco Male - Open
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Frequently Asked Questions
What is an RJ21 telco cable?+
An RJ21 is a 25-pair cable fitted with a 50-pin Amphenol-style "Telco" connector. It carries up to 25 voice or data lines in a single cable and is widely used to connect PABX phone systems, voice gateways and cross-connect frames.
What is Cat3 telco cable used for?+
Cat3 is voice-grade cabling used for telephone systems, PABX/PBX connections and low-speed data. It is the standard for connecting multiple phone lines between telco equipment, patch panels and distribution frames.
How many lines does a single RJ21 cable carry?+
One RJ21 connector handles 25 pairs (50 pins) — up to 25 separate phone lines or data channels in a single cable.
Are these compatible with Cisco VG224 and VG310 voice gateways?+
Yes. Our RJ21 leaded cables and panels are designed to connect directly to Cisco VG224, VG310 and VG320 gateways and other equipment using the standard Telco/Amphenol interface.
Can I order a custom length?+
Yes — every telco cable is made to order in our UK workshop. If you cannot see the length or connector configuration you need, contact us on 01488 685 400 and we will build it to spec.
How fast is delivery?+
In-stock items dispatch the same working day from our Hungerford warehouse, with free standard delivery on Mainland UK orders over £250.