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EFB-Elektronik RJ45 T-Adapter 1:1 Parallel, RJ45 Plug to 2 × RJ45 Jack, Cat.3, 15 cm, for ISDN and Telephone

Brand:
EFB
EFB RJ45 T-Adapter 1:1 Parallel Cat.3, 15 cm
EFB-Elektronik RJ45 T-Adapter 1:1 Parallel, RJ45 Plug to 2 × RJ45 Jack, Cat.3, 15 cm, for ISDN and Telephone
€9.97 inc. VAT
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K5125.015
€8.38
€9.97 inc. VAT
Ships from EU stock: 5 item(s)
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Product Code
04:261602
EAN Code
4049759022303
Manufacturer
EFB

Quick Specs

Type
RJ45 T-adapter, 1:1 parallel
Connectors/Interface
RJ45 plug → 2 × RJ45 jack
Key spec
Cat.3, all 8 pins parallel, 15 cm
Compatibility
ISDN / telephone — not Ethernet
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EFB-Elektronik RJ45 T-Adapter 1:1 Parallel — Two Jacks on the Same Line, for ISDN and Telephone

1:1 parallelPlug → 2 × jackCat.315 cm

The EFB-Elektronik K5125.015 is a Cat.3 RJ45 T-adapter that connects all eight pins of one RJ45 plug in parallel to two RJ45 jacks, for connecting two terminals to the same ISDN or telephone line — for example a phone and a fax or an alarm dialler on one outlet.

Because both jacks carry the same pins, they share one line. That is exactly what ISDN S0 buses and analogue telephone extensions need — and exactly what Ethernet cannot use.

Before you order: Do not order the wrong part: this K5125.015 is a 1:1 parallel adapter and will NOT split one Ethernet cable into two network ports. For two 10/100 Ethernet links on one cable, the part is K5126.015 (used in pairs).

What's in the Box

  • 1 × EFB-Elektronik RJ45 T-adapter 1:1 parallel, 15 cm

What It Means in Practice

  • Connect two ISDN terminals to one S0 outlet.
  • Add a second telephone device on the same analogue line.
  • 15 cm lead keeps the adapter close to the wall outlet.
  • Plug-and-play: no configuration, no power.

What Will Not Work

  • It will not work for Ethernet: two network devices on it will not get a link.
  • It is Cat.3 only — not for data cabling.
  • It does not create a second line; both jacks share the same one.
  • It is not a switch or hub.

Key Features

 
1:1 parallel
All eight pins go to both jacks.
 
Cat.3
Rated for voice and ISDN.
 
15 cm lead
Short cable to the RJ45 plug.

Technical Specifications

Identification
Part Number K5125.015
EAN / GTIN 4049759022303
MPN K5125.015
Brand EFB-Elektronik
Connectivity
Input 1 × RJ45 8(8) plug
Outputs 2 × RJ45 jack
Wiring 1:1 parallel, all 8 pins
Category Cat.3
Use ISDN, Token Ring, telephone
Physical
Cable length 15 cm
Warranty
Warranty 1-Year Warranty (Singular)
Manufacturer Term Manufacturer does not publish a warranty term — claims handled through Singular

Frequently Asked Questions

Can I use it to add a second PC?
No. For two network devices use a small switch, or the K5126.015 cable-sharing adapters in pairs (10/100 only).
Does it work with analogue phones on RJ11?
RJ11 plugs fit RJ45 jacks mechanically and the centre pins carry the line, so analogue phones generally work. Ask us with your setup to be sure.
Singular Expert Insight · Buyer's Guide
The two EFB T-adapters look almost identical but do opposite jobs: K5125 shares one voice/ISDN line, K5126 splits Ethernet pairs. For more network ports at a desk, a small switch from our network switches range is usually the best answer.
✓ Buy it if you need two ISDN or telephone devices on the same outlet.
✕ Skip it if you want to connect two network (Ethernet) devices.
→ Also consider EFB-Elektronik K5126.015 for 2 × 10/100 Ethernet cable sharing.
Not sure it fits your setup? Send us the model of your rack, switch or device and we will check compatibility before you order.

Features - EFB - K5125.015

More Details
Product Code
04:261602
EAN Code
4049759022303
Manufacturer
EFB
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