Bill Marr: Inventor of the Marrette®

Curiosity at the service of safety

At the turn of the 20th century, Bill P. Marr, a young Scotsman who had just arrived in Canada, had no idea that his ability to challenge the status quo would revolutionize the electrical industry.

While working as an electrician on the conversion of residential gas lighting to electric lighting, he found that the method of connecting wires together was tedious and dangerous. Electricians first had to buff the conductors before twisting them together to make the connection. The connection was then immersed in a molten solder bath, removed and allowed to cool, and then wrapped with insulating tape.

With a desire to do things differently, he set to work in his home’s basement workshop to find an alternative to the then current connection method. That is how the first pressure wire connector, branded “Marrette”, was created in 1914.

With over a century of history, this connector is now recognized everywhere, and it comes in many varieties. In recent decades, Bill Marr's legacy of innovation has continued with the creation of the Black® series - the first twisted models - including the Marrette 30, Marrette 31, Marrette 33 and Marrette 35 that are still sold today.

The XTP series was then developed and with it came color coding of the wire connectors. Several other innovations have been introduced over time. Most recently, ABB launched the PRO-BLU™ 933™, an ergonomic and versatile model with wings.

The story of Marrette wire connector told by Marc-Antoine Veillette

Listen to our product manager for fastening and wire termination tell the story of the invention of the Marrette wire connector in this short video.

Marrette® PRO-BLU™: our flagship wire connector

Our PRO-BLU™ 933™ product with ergonomic wings offers an easy and comfortable grip, making it easier for electricians to twist wires, even after installing multiple wire connectors.

The true-blue Marrette was designed and is manufactured in Quebec and can be used for most residential and commercial applications. Its main features include:

  • Wide and deep throat to ensure complete coverage of the wires;
  • Temperature resistance up to 125° C (257° F);
  • Variable volume Live Action® spring expands to allow connection of larger wire combinations with less twisting effort;
  • Rounded edge for safe and comfortable installation.
  • Approved for 600 V circuits and 1000 V lighting or signage;
  • Wide range of wire combinations from #22 to #8 AWG, solid or stranded, without pre-twisting.
Catalogue Number Description Quantity
933P Propak 100
933BK Flip-Pak 10,000
933BAR Barrell 25,000
933-JAR200 Plastic jar 200
933-JAR400 Plastic jar 400
933-JAR1000 Plastic jar 1,000

The Marrette family of wire connectors

Need to connect aluminum wires or connect electrical wires in a high temperature or vibrating environment? No matter what the application, we have a Marrette wire connector for you! Check out our different connector models and stop by your local distributor to stock up.


Ergonomic and safe, this wire connector is ideal for many types of installations, both residential and commercial, including heating units and thermostats.

Porcelain extreme high temperature

The most heat resistant of the Marrette family, the porcelain wire connector can withstand temperatures up to 645° C (1200° F). With no spring, this model is just as effective as our spring-loaded Marrette connectors because the inside surface of the cap is grooved to securely hold the conductors.

XTP® Series

Available in a variety of colors, the XTP series connectors are designed to address a wide range of needs and applications. They are approved for circuits of up to 300 or 600 volts depending on the model. Many wire combinations are possible from 1 #22 to 2 #8. Our convenient packaging is perfect for job site use!

Type II® winged

Made of thermoplastic polymer, a durable material that resists high installation pressures, this connector features longer ears than most other Marrette models for a better grip during installation.

Marrette Black® high temperature

The Black family of connectors is the first twistable type and is ideal for high temperature applications. This makes them a great option for wire connections for high-intensity lighting and signs.

Set-screw vibration proof

This Marrette wire connector features two separate parts: a brass bushing and an insulating screw cap. Recommended applications for this connector include motor replacements, circuit additions and temporary wire connections. This design is very similar to the first wire connector invented by Bill P. Marr in 1914.

ACS® aluminum wiring (brown)

As the name suggests, this connector is designed for aluminum conductors and is CSA approved for copper-to-copper, copper-to-aluminum and aluminum-to-aluminum connections. The springs are made of a special alloy and coated with a tin layer for superior corrosion resistance and to meet industry standards.

Get our Marrette wire connectors now!

Check our online inventory and find the distributor of your choice to place an order. Do not hesitate to contact us if your supplier is not listed.

© 2024 ABB Electrification Canada Inc.