4 Way Flat to 7 Way Round Trailer Adapter Plug Nilight
4 Way Flat to 7 Way Round Trailer Adapter Plug Nilight
4 Way Flat to 7 Way Round Trailer Adapter Plug Nilight
4 Way Flat to 7 Way Round Trailer Adapter Plug Nilight
4 Way Flat to 7 Way Round Trailer Adapter Plug Nilight

4 Way Flat to 7 Way RV Trailer Blade Adapter Plug

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About this item

  • This adapter converts a 4-way flat vehicle end to 7-way blade trailer end, makes the tight connection between vehicle socket and trailer plug, no wiggle-room, no loose fittings. Transfers the power from the vehicle to the trailer. voltage range: 6-24 Volts
  • 4-pin flat socket designed to be converted to the 7-pin blade round type socket. Works on most vehicle wiring components like turn signals, brakes, reverse light, and auxiliary power.
  • Heavy-duty black plastic construction prevents rusting and enhances appearance. Well, the sealed spring-loaded cover increases protection against dust, moisture, and corrosion.
  • Wide Application: Suitable for most trailers, semitrailers, caravans, and RVs. Commonly used with T-connectors or tail lamp converters with 4-way flat car end connections
  • Package includes 1x Trailer Adapter Plug, 1x Mounting bracket 6 screws, and 6 nuts.

4 flat to 7 way RV trailer adapter plug

4 Way Flat to 7 Way Round Trailer Adapter Plug

Well transfers the power from the vehicle to the trailer/RV

Allows a connection to be made between a mismatched trailer plug and vehicle socket. It easily plugs in your vehicle's electrical socket and usually requires no additional wiring Works on most vehicle wiring components like turn signals, brakes, and auxiliary power Applicable for utility RV boat camper trailer car carrier, allows the user to create custom plug-in wiring systems for any towing situation.

  • Wiring harness Connection:
  • Yellow Wire (from 4-Way Plug): Left turn signal
  • Brown Wire (from 4-Way Plug): Taillights
  • Green Wire (from 4-Way Plug): Right turn signal
  • Yellow Wire: Spare wire, backup
  • White Wire: Attach to a vehicle ground point
  • Blue Wire: Connect to the output wire on the brake controller
  • Black Wire: Connect to fuse block or fused battery lead


Spring-loaded Protective Cover

Spring-loaded Protective Cover

A well-sealed spring-loaded dust cover keeps the adapter clean when not in use, and increases protection against dust, moisture, and corrosion.

Mounting Bracket Included

Mounting Bracket Included

The 4-pin to 7-pin trailer adapter plug includes a mounting bracket and screws and nuts that allows the user to create a custom plug-in wiring system for any towing situation

Reliable Design

Reliable Design

Slit loom keeps wires contained and well protected. Concealed terminals help ensure a reliable connection.

Customer Reviews

Based on 41 reviews
Joseph S.
4 Way Flat to 7 Way Round Trailer Adapter Plug

This product was as described and installed easily. I would recommend this product to others. Good value compared to other similar products.

Robyn Bogisich
Great Product

Great to do business with. Thank you

Addie Romaguera
Works as it should

I had issues with this blowing fuses on the blinkers so I purchased another brand. It also blew fuses. I assume I have bad wiring in my vehicle that must be found, now. Unfortunately, it works for a little while , thne blows a fuse, so the short must be intermittent.

Lazaro Funk
Perfect for DIY brake controller

Boy do I wish I knew then what I know now...Long story short, I bought the wrong vehicle for towing. Although it can tow up to 3,500 lbs it came with only a 4-pin connector at the back (Just lights, basically).What the dealerships and commercials don't tell you is "upgrading" to a 7-pin requires splicing into the wiring under your dash and connecting a wire up to your battery. It voids your warranty!This thing can adapt your 4-pin to a 7-pin, allowing you to connect a trailer to your truck/SUV... It does not provide the brake signal or power, you have to do that. For power, I recommend a 12V cigarette-lighter adapter. I got one on Amazon and I connected it to this adapter (You connect it to the black wire) to provide 12V (grounded) power to the trailer.For the brake-signal, if your trailer has electric-brakes, check out the wireless brake controller from CURT ("CURT Echo").I did not use the mounting bracket because I wanted to have a full brake-controller setup that I can quickly disconnect/remove (Leaving nothing behind, not even a screw hole...).

Elnora VonRueden

Easy to install

Alicia Pollich
Great when used with the Potsdam magnet tail lights.

Will post video when install is complete

Emory Zemlak
Can't beat this price for what you get

This bracket is very sturdy. Everything works as expected. My truck did not have a 4 pin connector so I just had to cut the 4 pin connector off the end of it and strip the wires. Didn't take long to get the blinkers, tail lights and brake lights working at all. My truck even had a hot accessory wire just sitting there waiting for me to hook up. I'll probably never need the accessory power, but it's wired up if I ever do need it. The blue electric brake wire is another story. I have a blue wire but I don't think it is hooked up to anything at the front of the truck. Hopefully one day I'll have some spare time to troubleshoot it. I also did not hook up the reverse lights wire, but my trailer doesn't have reverse lights anyway.

Margarett Jerde
Very easy install

Harness for trailer hitch, plug and play

Corine Denesik
Buena calidad de materiales, todo lo necesario para instalar

Este es un conector alternativo al equipo OEM que traen algunos vehículos, pero es de buena calidad y el precio es accesible.

Marcus Ullrich
Good quality

Very easy to use and good quality

Parts ordered must be in stock for the order to ship. Approximately 98% of all orders placed leave our warehouses the same day (not including weekends & holidays). Even with our huge inventory, we may run out of an item. If this is the case you will receive an email with an expected availability date.

DELIVERY DAYS: 2-6 Business Days (More Time and Extra Fee for * Heavy and Big-size Products ) Processing Time: 1-2 Business Day

Free Shipping

Qualifying items receive Free Shipping on all orders. Qualifying orders for Free Shipping are shipped via ground delivery. Free Shipping is only applicable to the continental United States. Excludes Alaska, Hawaii, and Other Countries. Please check the detail page to see if it qualifies for Free Shipping. 

Return Policies

Nilight will accept returns for up to 30 days from the date of purchase. Please include all original items in your return shipment. Incomplete returns may not be eligible for a full refund. Returns within 30 days or purchase will receive a full refund for the purchase price of the product. 

No returns will be accepted after 30 days. Nilight will provide a return shipping label upon request. 

Non-contiguous US residents and International residents – including Alaska, Hawaii, Canada and Mexico – are responsible for return shipping charges. Refunds will be applied to the original payment method that was used. Refunds are generally issued within 5-10 business days of Nilight receiving all returned goods. Your bank may require additional processing time to reflect the refund in your account.
A section of our product offering requires a warning related to California’s Proposition 65, officially known as the “Safe Drinking Water and Toxic Enforcement Act of 1986”. In the links below, you will find a list of products along with the chemical in question. To adhere to the guidelines of California’s Proposition 65, these products must be labeled with a warning, of which you will find an example below. Due to the reach of our products and the inventory streams they bring, it may take some time before products reach the end users with these warnings. 

If you carry Nilight products on your shelf, and those products match the products on the list, we advise you place the attached warning on them. Additionally, if you advertise our products on your website, the products on the attached list must have warnings with them on the webpage. Nilight is willing to work closely with our valued customers to successfully adhere to California’s Proposition 65. If you have any questions regarding this communication, feel free to reach out to our customer service team.

To find out more about California’s Proposition 65 and requirements, please visit their website at https://www.p65warnings.ca.gov/

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