I tested the polarity and the coupler changes the polarity of the lines compared to when polarity checked at outlet before coupler used. PIN layout?

Yes, many of these couplers are simple, straight thru pin 2-5 to 2-5 and do not properly crossover/reverse the pins to maintain the continuity on the same wires throughout both cables. If using this type of straight thru coupler, you'll need to either use two of them (plus an extra "bridge" cable) or wire up your own custom crossover cable to correct the pin-out issue.

Does this work for two-line phones?

If there are two lines connected to the phone that you want to extend with "extension chords" (connect to longer phone lines), you would need on coupler for each line.

Fully operational. Shipping worldwide, on schedule.Customs & duties included in the price

Help Track order

Account Cart

Fully operational. Shipping worldwide, on schedule.Customs & duties included in the price

Help Track order

Account Cart

RFAdapter RJ11 Coupler, 2 Pack Telephone Phone Line Connector Coupler RJ11 6P4C Inline Keystone Jack Female to Female Straight Telephone Cable Cord Extension White

RFAdapter RJ11 Coupler, 2 Pack Telephone Phone Line Connector Coupler RJ11 6P4C Inline Keystone Jack Female to Female Straight Telephone Cable Cord Extension White

Product ID: 378141472

Details

Brand
RFAdapter
Cable type
Telephone
Compatible devices
Telephone
Connector type
RJ11
Special features
Compact

📞High Fidelity Sound Quality

🔌RJ11 Female-to-Female Connector

🛡️Strong Anti-Interference & Low Signal Loss

€ 12.46

Duties & taxes included

In stock

Sold byAmazon GERMANYDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to GERMANY.

Secure transaction

Description

📞 Connect with clarity, extend with confidence!

CRYSTAL CLEAR CALLS - Experience high fidelity sound with zero static, ensuring professional-grade communication.
RELIABLE WORRY FREE - Backed by a 12-month warranty and responsive customer service for total peace of mind.
SEAMLESS LINE EXTENSION - Effortlessly connect and extend your telephone lines without signal drop or distortion.
UNIVERSAL COMPATIBILITY - Works flawlessly with all RJ11 devices—landlines, fax machines, and answering systems.
COMPACT DURABLE DESIGN - Space-saving, sturdy build fits discreetly in any office or home setup.

The RFAdapter RJ11 Coupler 2-Pack offers a compact, durable solution to extend telephone lines with female-to-female RJ11 connectors. Designed for crystal-clear, high-fidelity sound and strong anti-interference performance, it ensures zero signal loss across all RJ11-compatible devices. Ideal for professional and home environments, it comes with a 12-month warranty and trusted customer support.

Specifications

ASIN	B08L67FQ8T
Best Sellers Rank	#72,370 in Electronics ( See Top 100 in Electronics ) #110 in Telephone Cables
Brand	RFAdapter
Brand Name	RFAdapter
Cable Type	Telephone
Cable type	Telephone
Color	White
Compatible Devices	Telephone
Compatible Phone Models	All Smartphone
Compatible devices	Telephone
Compatible phone models	All Smartphone
Connectivity Technology	RJ11
Connector Gender	Female-to-Female
Connector Type	RJ11
Connector type	RJ11
Customer Package Type	FFP
Customer Reviews	4.6 out of 5 stars 659 Reviews
Ethernet Cable Category	Cat 5
Indoor Outdoor Usage	Indoor
Item Shape	Round
Manufacturer	RFAdapter
Model	RFAdapter Telephone Wires
Number of Items	2
Number of Pins	6
Other Special Features of the Product	Compact
Part Number	ULRF0A0135A-2-CA
Recommended Uses For Product	telephone line extension or combination
Special features	Compact
UPC	744306795542
Unit Count	2 Count

Reviews

R**G

It works great

Did not have 1 long enough cord to connect phone/fax machine to phone jack but this coupler did great job of connecting the two cords.

12.06.2025

S**A

ELOGIO

Ótimo. Atendeu às minhas necessidades. Recomendo.

28.03.2025

A**Z

Satisfecho!

Buen producto

30.01.2026

E**R

Know what your source of the TIP and RING and on what pins each are located

If this product is used you need to know how your system is configure

18.10.2021

B**A

Happy to know it's availablity .

item arrived on time and worked great.

26.05.2025

Common Questions

Are the products genuine and authentic?+

Yes, all products are sourced directly from authorized retailers in the US, UK, UAE and India. We maintain strict quality control processes and verify each product before shipping. All items come with applicable manufacturer warranties and are covered by our standard return policy.

How long does delivery take and is it reliable?+

Delivery times vary by destination country, typically ranging from 3-9 business days. Each order is fully trackable through our system. We handle all customs clearance and use reliable courier partners for last-mile delivery. You'll receive regular updates about your order status via email and our app.

What is Desertcart? Is it safe to order from?+

Desertcart is an international e-commerce platform operating since 2014. We securely process thousands of orders globally each day. Every product goes through our quality verification process before delivery, and we provide end-to-end order tracking, 24/7 customer support, and a comprehensive returns policy to ensure a safe shopping experience.

How is product pricing calculated?+

Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Yusuf A.

Fantastic experience overall. Will recommend to friends and family.

1 month ago

Farhan Q.

The delivery time was excellent, and the packaging was secure.

2 months ago

View all Trustpilot reviews

Shop Global, Save with Desertcart

Value for Money

Competitive prices on a vast range of products

Shop Globally

Serving millions of shoppers across more than 100 countries

Enhanced Protection

Trusted payment options loved by worldwide shoppers

Customer Assurance

Trusted payment options loved by worldwide shoppers.

Desertcart App

Shop on the go, anytime, anywhere.

€ 12.46

Duties & taxes included

In stock

Sold byAmazon GERMANYDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to GERMANY.

Secure transaction

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Zainab N.

Fantastic and great service. Shipping was faster than expected.

1 week ago

Neha S.

Excellent communication throughout the order process. Product is perfect.

2 weeks ago

View all Trustpilot reviews