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Custer Trailer Connector Adapter w/ Dust Cover - 7-Pole Round Pin to 7-Way Blade
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Brophy

Custer Trailer Connector Adapter w/ Dust Cover - 7-Pole Round Pin to 7-Way Blade

Part Number: F77R
51 Reviews | 21 Questions
$56.79
 Custom Fit Vehicle Wiring
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This adapter converts your 7-way round pin connector to a RV-style, 7-way blade connector. Built-in ABS plastic cover protects the 7-way blade terminal from dust and moisture. Pull grips on the round end make the plug easy to install and remove. 1-800-940-8924 to order Brophy custom fit vehicle wiring part number F77R or order online at etrailer.com. Free expert support on all Brophy products. Great prices and Fastest Shipping for Custer Trailer Connector Adapter w/ Dust Cover - 7-Pole Round Pin to 7-Way Blade. Custom Fit Vehicle Wiring reviews from real customers.
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Brophy Custom Fit Vehicle Wiring - F77R

Highlights

  • Connect Round to Blade: Links a 7-pole round trailer plug to a 7-way blade vehicle socket.
  • Tow Without Rewiring: Lets mismatched 7-way connectors work together with no wire changes.
  • Quick Plug-In Use: Adapter plugs directly into existing 7-way for instant connection.
  • Protects Contacts: Built-in dust cover keeps terminals clean between tows.
  • Universal Fit Design: Works across vehicles and trailers using standard 7-way wiring.

Features to know about

Connects Different 7-Way Styles: 7-Pole Round Pin to 7-Way Blade Adapter

When your truck and trailer don’t share the same 7-way connector style, this adapter bridges the gap. The Brophy Custer Trailer Connector Adapter w/ Dust Cover (part # F77R) plugs into a vehicle’s RV-style 7-way blade socket and provides a 7-pole round pin connection for the trailer. It’s a simple plug-and-play fix that gets you towing without rewiring or replacing connectors.

Close-up image of the Brophy Custer Trailer Connector Adapter F77R with dust cover closed, showing durable black housing and compact design.

Ready for Heavy-Duty Towing: Solid Plug and Lead Design

This adapter is built with a sturdy plug and lead design that holds up under constant use. It fits snugly and stays connected, even on rough roads or when pulling heavier trailers. The firm connection keeps your lighting and brake signals working reliably from truck to trailer.

Protects Against Dirt and Corrosion: Built-In Dust Cover

Keeping your terminals clean matters for long-term performance. The built-in dust cover shields the round socket when not in use, keeping out moisture and debris. That protection helps maintain strong electrical contact every time you hook up your trailer.

Universal Fit for Flexible Use: Works Across 7-Way Systems

Whether you’re towing a utility trailer, camper, or equipment hauler, this universal-fit adapter handles the job. It lets you connect gear with different wiring styles without modifying either end, making it a handy piece to keep in the toolbox for any towing setup.

Specs

Electrical and Compatibility

  • Type: Trailer Connector Adapter
  • Connector 1: 7-Pole Round Pin (trailer side)
  • Connector 2: 7-Way Blade (vehicle side)
  • Application: Adapts trailer with 7-Pole Round connector to vehicle with 7-Way Blade connector
  • Manufacturer: Brophy
  • Product Title: Custer Trailer Connector Adapter w/ Dust Cover - 7-Pole Round Pin to 7-Way Blade

Technical diagram showing the Custer Trailer Connector Adapter F77R with labeled pin positions for converting from 7-pole round pin to 7-way blade connector.

Features

  • Included Component: Dust cover
  • Fitment: Universal Fit

F77R Custer Trailer Connector Adaptor with Dust Cover - 7-Pole Round to 7-Blade







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Customer Satisfaction Score:

Ratings & Reviews

4.6

51 reviews
5 Stars
(43)
4 Stars
(3)
3 Stars
(1)
2 Stars
(0)
1 Star
(4)
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by:
etrailer is a great vendor and has always had in stock what we needed. Thank you!
by:
I have ordered several of these in the past from etrailer. Great product, quick shipping, an overall Great company to do business with.
Jeff K. profile picture

Jeff K.

9/21/2017

Ive heard no complaints from our employees who use these.

by:
This product did not work. The diameter of the 7 pin receptacle plug was 1/8” narrower than my trailer plug. It fit perfectly into the 7 way blade receiver plug on my truck. I called customer service. She called manufacturer and manufacturer said there must be something wrong with my trailer plug. My trailer plug came standard on the trailer. Unfortunately no inside diameters are provided so one cannot measure before ordering. I am returning the product but was told I have to pay for shipping. etrailer has such a good reputation. I am really disappointed in this experience.
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Jenny N. profile picture
Etrailer Expert

Jenny N.

10/25/2021

I will have our customer service team reach out to you. This adapter is intended to work with most 7-way blade, RV-style trailer side plugs.

by:
Exactly what we were looking for. Customer service was great and found the right product for our application in a few minutes, shipping was quick. We are on the road with lights and no rewiring.
by:
Received quickly, worked with brake lights & turn signals, but not headlights or parking lights
by:
Worked well as adaptor from Great Plains no till drill wiring harness to use on truck.
by:
Product didnt work for my application even after talking to a tech and explaining what i needed after i returned the original i ordered so yeah good luck
by:
Worked perfectly. Nice for towing farm equipment with a normal common plug from truck. Works great on my Ford trucks.
by:
Worked as listed. E-trailer has provided yet another good product delivered on time. Thanks
by:
I placed two orders recently. The website is organized and I was able to find what I needed. I spoke with Customer Service and they were nothing but helpful. I will definitely use them again.
by:
We have ordered 2 of these for our shop and love them. great quality not cheaply made. great customer service and fast delivery.
by:
Looks Heavy-Duty. We'll see how wiring matches-up!
by:
Best adapter for the money. I am using it on farm equipment, so i can have lights when I tow with my truck.
by:
Works perfect for 7-round to 7-flat.
by:
worked fine. was very well made. i used it to pull my Deere baler with the ton truck to the dealer for repair. it'll be on hand for many years for that use.
by:
Works exactly as intended. I don't use it a lot, but I am happy with it.
by:
Good product
by:
Works great, Had to switch a few wires other than that works perfrect.
by:
Was exactly what I wanted. The pictures online made it easy to identify the correct product so it was great to get the right part the first time and on time.
by:
Been looking for this application locally for a while. Happy to find it here. Haven't used it yet but it looks well made.
by:
GREAT SERVICE GREAT PEOPLE TO DEAL WITH WAITED A LITTLE LONG FOR THE PART BUT OTHERWISE GREAT PRODUCTS THANKS AGAIN STEVE
by:
Product showed up in a couple of days and works exactly as advertised , I couldn't of been happier with the whole experience.
by:
Just what was needed
by:
Useful adapter
by:
Nice item.
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Do you have a question about this Custom Fit Vehicle Wiring?


Info for this part was:

Employee Dan D
Written by:
Dan D
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Jeff D
Installed by:
Jeff D
Employee Wilson B
Updated by:
Wilson B

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