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7-Way Round RV Style Trailer Connector - Trailer Side

7-Way Round RV Style Trailer Connector - Trailer Side

Item # A7WCB
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7-Way round plug lets you connect your trailer to the 7-way round blade connector of your tow vehicle. Interlock system keeps connections in place. Over-sized finger grips for secure disconnections. Durable ABS plastic housing. Great Prices for the best trailer wiring from Optronics. 7-Way Round RV Style Trailer Connector - Trailer Side part number A7WCB can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (306)
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Optronics Trailer Wiring - A7WCB

  • Trailer Connectors
  • Trailer End Connector
  • 7 Round - Blade
  • Plug Only
  • Optronics

7-Way round plug lets you connect your trailer to the 7-way round blade connector of your tow vehicle. Interlock system keeps connections in place. Over-sized finger grips for secure disconnections. Durable ABS plastic housing.


  • 7-Way round plug lets you connect your trailer to the 7-way round blade connector of a tow vehicle
  • Interlock system locks in place to keep connections secure
  • Over-sized finger tabs allow you to easily grip the plug during disconnections
  • Adjustable insert tightens against wires to limit exposure to dirt, dust, and water

A7WCB Optronics Replacement 7-Way Round RV Style Trailer Connector - Trailer Side

Alternate part: A-7WCB

Compare to Bargman 54-77-003

California residents: click here

Video of 7-Way Round RV Style Trailer Connector - Trailer Side

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Review of Optronics Trailer Wiring - 7 Way Round RV Style Trailer Connector To Blade - A7WCB

Hi, everybody. Andy here with And today we're gonna take a real quick look at this seven-way round RV style trailer connector. This seven-way round plug is going to let you connect your trailer to your seven-way round blade connector of your tow vehicle. And this features a durable ABS plastic housing and the interlock system is going to lock in place to keep your connection secure. The oversized finger tabs are going to allow you to easily grip the plug during disconnections.

And I wanted to point out a few things here. On this end, on this side here of this connector, we have these two set screws that's going to loosen and tighten this insert. So when you begin to run your wires through this connector, you obviously want to loosen these screws up and that's going to allow that insert to move out of the way. So then you can begin to run your wires through there and then you can just tighten these two screws back up and that will in turn tighten up that insert and that's going to close, that's going to close up against the wires that you run through here, giving you a nice, tight, secure fit. So that's going to keep out dust and moisture out of those connection points.

And then I wanted to point out this other screw that we have here on the other end on top, that's going to allow this connection point to actually come out of the housing. So you're gonna run your wires through, get this portion out and make your connections and then put it back into the housing and then tighten the screw. Well, that's gonna conclude our brief look today. I do hope that it was helpful for you. Again, my name is Andy.

Thank you for joining me.

Customer Satisfaction Score:

Customer Reviews

7-Way Round RV Style Trailer Connector - Trailer Side - A7WCB

Average Customer Rating:  4.7 out of 5 stars   (306 Customer Reviews)

7-Way round plug lets you connect your trailer to the 7-way round blade connector of your tow vehicle. Interlock system keeps connections in place. Over-sized finger grips for secure disconnections. Durable ABS plastic housing.

by: 07/21/2023

I was expecting blade connectors as shown in the pictures and video and that is the main reason I purchased this item. Instead it had screw connectors.

Etrailer Expert

Brooke M.


Thanks for letting us know! I will have our customer service team reach out to you about this.


Works great, easy to install


Parts arrived quickly and were very good quality. I will definitely use for all my trailer supplies.


I was hoping for the terminal blade connectors, like the video shows, instead of the screw type connectors that I got. The blade connectors seem to be more reliable. Still, it's a quality plug, it's installed and it works. Thank you.


It would have been very helpful if the item description would have stated that the trailer connector was equipped with "Spade Contacts" and require Spade Connectors, and/or illustrate this in a picture, and provide those connector as part of the package. It would have saved a lot of time in making a second order to acquire the Spade Connectors.


Perfect fit to change our trailer from a 5 pin to a 7 pin with added capabilities. we are long time etrailer customer and they always ship fast and have affordable prices to suit our needs.


Great People to deal with and very prom pt


JUNK! Steel screws to connect brass connectors! just a matter of a short time before corrosion.


After a year it still does as it should


My order got lost in shipping and eTrailer took care of the shipper's problem and promptly sent out another item. Great service.


Very helpful and friendly and always has what l need


A great business with quality products!


Perfect fit. Easy to use. Great product. Using this to help trickle charge a battery for the trailer winch.


We have an older 5th wheel and needed to change out the connector to match up with our new tow vehicle. The connection worked out perfectly!


should work okay. would have been good to have some directions

Etrailer Expert

Jenny N.


Yeah a part like this does not come with written instructions. I recommend taking a look at the review video we have below.


It works, only a single connection pet plug while other have 2 per plug section. We will see how oong it will hold up



Works perfect and has been holding up in the weather here in new England


Used this as a plug for my portable 12V air compressor to facilitate access to power, rather than clips to battery. As usual, over the past several years etrailer is my go-to store for all trailer & towing needs. Excellent variety, price and prompt service. Keep up the good work..............



We installed the lights on a trailer we were selling. Installation went smooth, lights worked great.We install the trailer plug on a 12V compressor so we could power it from our trailer hook up and it works great also. You are our go-to trailer supply store.


Wired it in and it works. Not much more to say. Works on my buddy's 2006 F-150 and on my 2003 Dodge Neon ( heard that right) and also on my 2016 Sierra Denali.


Good quality.


Easy to wire and the hard mounted contacts solved the intermittent connection issue I was having with the previous connector that had floating contacts.


works great


Had to replace a 7 pin on an RV that got sheered by previous owner. The video on how to replace and the part made it very easy to change the connector. Saved a bundle doing it ourselves.



Still going strong


Very good quality, fast shipping.


Great product best price and fast deliv ery


Good hookup works as expected.

Show More Reviews

See what our Experts say about this Optronics Trailer Wiring

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