bing tracking image
  1. Trailer Wiring
  2. Pollak
  3. Trailer Connectors
  4. Vehicle End Connector
  5. 7 Round - Round
  6. Plug Only
Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End

Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End

Item # PK11720
Our Price: $12.03
You Save: 58%
Trailer Wiring
Add to cart
In Stock
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

Customer Photos


Need help with installation?
Locate installers near me
Establish a secure connection between your trailer and semi or other tow vehicle with this 7-pole, solid pin, wire-insertion-style socket. Zinc die-cast socket is self-grounding and includes floating pins for easy alignment and maximum pin contact. Great Prices for the best trailer wiring from Pollak. Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End part number PK11720 can be ordered online at or call 1-800-940-8924 for expert service.
  • All Info
  • Reviews (132)
  • Q & A (0)
  • Photos

Pollak Trailer Wiring - PK11720

  • Trailer Connectors
  • Vehicle End Connector
  • 7 Round - Round
  • Plug Only
  • Pollak

Establish a secure connection between your trailer and semi or other tow vehicle with this 7-pole, solid pin, wire-insertion-style socket. Zinc die-cast socket is self-grounding and includes floating pins for easy alignment and maximum pin contact.


  • Zinc die-cast 7-pole socket connects trailer to towing vehicle
  • Round, floating, solid brass pins
    • Easy alignment and maximum contact
    • Minimum voltage drop is ensured
    • Dielectric (non-conducting) grease coating
      • Protects against corrosion and resistance
    • Wide range of wire gauges acceptable, from #16 wire to #8 ground wire
      • Ground terminal accepts minimum #14 gauge - maximum #8 gauge
      • All other terminals accept minimum #16 gauge - maximum #10 gauge
  • Self-grounding to #1 Ground Terminal
  • Slant-mounted with built-in drain slot on cover
    • Rids housing interior of accumulated moisture
    • Opens and closes with stainless steel spring
    • Bottom lip extended for better plug support
  • 2-Hole mounting style
  • Highest quality - meets and exceeds all standards of SAE J560
  • Interchangeable with all competitive makes


  • Mounting dimensions: 2" diameter hole
  • Volt rating: 6 volts - 28 volts
  • Current rating: 40 continuous-duty amps
  • Wiring configuration:
    • Color - circuit - recommended wire gauge:
      • White - Ground Return - 10 gauge (FMVSS-121 Anti-lock Gauge - 8)
      • Black - Clearance, Side Marker, Identification - 12 gauge
      • Yellow - Left Turn and Hazard Signal - 12 gauge
      • Red - Stop Lamps and Anti-Lock Devices - 10 gauge (FMVSS-121 Anti-lock Gauge 10)
      • Green - Right Turn and Hazard Signal - 12 gauge
      • Brown - Tail, Rear Clearance, Marker and License-Plate Lamps - 12 gauge
      • Blue - Auxiliary Circuit/ABS - 10 gauge
  • 1-Year limited warranty

11-720 Pollak Heavy-Duty, 7-Way, Round Pin Trailer Wiring Socket - Vehicle End
Replaces 52016

Customer Satisfaction Score:

Customer Reviews

Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End - PK11720

Average Customer Rating:  4.9 out of 5 stars   (131 Customer Reviews)

Establish a secure connection between your trailer and semi or other tow vehicle with this 7-pole, solid pin, wire-insertion-style socket. Zinc die-cast socket is self-grounding and includes floating pins for easy alignment and maximum pin contact.


Not using on a trailer, but making disconnect harness for quick attach snowblower to loader arm. Connection cord is 7 pin tractor trailer tether, Worked well.


Product is high quality & works great!

beat etrailer


Great Product. Just remember to order the boot for the back of it separate.


Awesome product selections and quick response towards shipping. Made me feel like I was actually getting somewhere. If you have a trailer, camper, or any type of tow behind application get HOOKED UP with this company. Very satisfied

Toby N.


I hook and unhook my trailer about twice a day as I need my truck for hauling stone and dirt. I have put this through the ringer. Still good as new...Happy customer


Trailer plug works great.


I would highly recommend this. It is heavy duty and quality built. A great value for the money


I ordered the 7 pole socket (PK11720) and the rubber boot for it. (PK11761) Also a trailer end plug (PK11700) to fit into the socket. The items arrived on the exact estimated arrival date that I was given on the day of ordering.
Wiring the plug and the socket was very easy. Each terminal has a small screw that holds the end of the wire in place. It is a simple matter of threading the screw out, putting the wire in the hole, and then tightening the screw onto the wire.
The boot fits snugly onto the back of the socket.
I used these parts to repair the power cable assembly to a truck mounted forklift. The parts are exactly what was needed to replace what had been damaged. The quality is good and the prices are excellent. I will use in the future when I need related items. I am very pleased.


Excellent product! - have, over only a few years, steadily worked my way through progressively more durable trailer cable sockets. The last one was the Hopkins heavy-duty, or something to that effect. The plastic casing on it broke within three months. I'm really looking forward to putting these to the test - I'm a farrier - I pull a trailer every day; the traffic in this area means that I must rely on excellent contact between vehicle/trailer for turn / brake signals and functioning trailer brakes. Nothing less. These sockets are heavy, all-metal (zinc-coated - road salt shouldn't be a problem), with few / no seams. When the trailer end is plugged into the truck receiver - it's a nice tight fit, with no movement: it's locked in. There are only two drawbacks for the homeowner who is looking for the do-it-yourself package: if you are looking for a metal bracket that bolts underneath the truck bumper and holds this part - there isn't any. And no bolts, either. I don't know if they sell them for these - I didn't check. I simply manufactured my own. So far, I'm delighted with the product.


This is much better than the OEM on my New Holland Tractor asit is made of metal. It also cost less than the all plastic replacement from the dealership. etrailer was fast with delivery. Thank you.

John G.


It is working out very nicely, really glad I bought it!


Bought to replace a 12 year old Pollak identical connector that I removed and could not re-use due to wire connections on the back being corroded (road salt area). The 12 year old connector worked fine except the flip up cover was a bit stiff. The 12 year old connector was also made in USA. The new connector I just received is made in China. From the price, I had hoped it was still made in USA. It seems that most of the time I am disappointed with the newer imported China versions of products once manufactured in USA. So my expectations for this product to have a long life are not very high.


I got exactly what I expected. Great customer service & follow through.



This is a quality socket that is being used to support electrical connections between my RV and toad. Its held up beautifully & I continue to be very pleased with it.


Quality product arrived on time. Will make future purchases with

Mike M.


Performed as expected to date.


Well I have not installed it yet, but it is marked for each trailer wire by color, matching much earlier models. Did not come with mounting screws and nuts, but not a big deal.


I could not find this style or make trailer plug in my local auto parts store. I got tired of trying to find it so I ordered it on line. etrailer was convenient and less expensive than any other website.


For me, and probably you, is a great place to shop/buy quality products. They give great follow up after ordering and fast shipping @ a fair price. I believe their service & pricing is unbeatable. I do shop for bargains & etrailer is @ the top of my list.


Again, high quality and a great brand. The wiring diagrams assisted me with understanding a difference between round pin and blade styles. I bought both with confidence for my F-350.


The metal body and good quality pins and connections make this one the only one for a professional job.
Remember if you use dielectric grease and the rubber boot you'll never have corrosion in your connections . Dissimilar metals and weather are a bad combination.


This item worked well for my application. It is bigger than I expected but I'm anticipating good performance!


Excellent product! I bought this to replace the old, brittle, and broken plastic trailer connector on my 1973 aluminum camper. The plastic one stood out against the aluminum which I didn't like. So, I'm excited how this will blend in and look more natural. Besides aesthetics, this very sturdy and ruggedly built. It will clearly outlast the camper, no doubt. Will definitely buy again if I find myself with a different camper in the future.


Etrailer web site was easy to work with and outstanding communication with your orders. Package was also delivered earlier than expected. I would rank etrailer as A+


This trailer lighting socket is excellent quality, and super fast shipping


Very fast service AGAIN! Always my first choice when shopping for trailer parts.


Great construction of the product, durable enough to withstand harsh working conditions and "operators" I am using that term lightly due to the mishaps that occur on a regular basis at my location.


Best 7 pole connector out there!!!!


Hi quality, perfect for my application

Show More Reviews

See what our Experts say about this Pollak Trailer Wiring

  • Parts Needed to Tow Trailer with 7-Way Blade Connector with 7-Pin Connector Off of Commercial Dump
    We do have exactly what you are needing to tow a trailer with the standard 7-Way blade with your commercial dump. To combine the turn/brake signals from your tow vehicle you simply need to use the Roadmaster Brite-Lite Wiring Converter # RM-732. After making those connections use a 7-Way blade connector like the Hopkins Endurance # HM47210 for a dedicate connector for the trailer. Just connect the following wires from the Hopkins Endurance to the following functions on your tow vehicle: White...
    view full answer...
    Image 1 for Image 2 for
  • Locating Cold Side of Brake Light Switch for 2000 GMC Sierra 3500
    I was not able to locate the wire color for the cold side of the brake light switch on your 2000 GMC Sierra 3500. Your best bet is to simply test the wires above the brake pedal to find the one that only receives power with the brake pedal depressed, and no power with any other function. This is really the best method even if you have a good idea as to the correct wire color, as vehicle manufacturers often change the color wiring they use at the factory. If you are looking to install...
    view full answer...
  • The Two Ways that Trailer 7-Way Wiring Colors are Used
    This is a really good question! So it turns out there are two ways that 7-way wire colors are ran. The one like what you described is considered 7-way traditional whereas the other style is considered RV standard. I attached a diagram that hopefully better explains the difference.
    view full answer...
    Image 1 for
  • Locating Cold Side of Brake Light Switch on 2013 Chevy Equinox
    The best and safest way to determine which wire is the cold side of the brake light switch on your 2013 Chevy Equinox is to simply test them with a circuit tester like # PTW2993. You are looking for the wire above the brake pedal that only receives power with the brake pedal depressed and no power with any other function. The correct wire on earlier model years of your Equinox was light blue with possibly a white stripe. You can start by testing this wire. Since vehicle manufacturers...
    view full answer...
  • Adding 4- to 7-Way Adapters on a 2000 Toyota Tundra and 2013 Toyota Sienna with 4-Ways
    Adapter # 47405 is probably not the adapter you need. It would plug into a 7-Way round pin connector on the tow vehicle and allow you to plug in a trailer that has a 4-Way flat connector. Since both of your tow vehicles have a 4-Way flat you will need different adapters. Also, there are 2 kids of 7-Way connectors. One has round pins like # PK11720 and the other, much more common and probably what the trailer will plug into, is a blade style like # PK11893. If the trailer has a 7-Way then...
    view full answer...
  • Finding Stoplight Signal Wire In 2018 GMC Canyon To Install Brake Controller
    We had the chance to install a P2 brake controller part # 90885 in a 2018 Chevy Colorado (same as a GMC Canyon) and we found the brake light signal switch to be white with a blue stripe. Check out the install video I attached to see the whole process.
    view full answer...
  • Does 12 Volt Pin of a Trailer Connector Have Power All the Time
    The auxillary or 12 volt power circuit on a 7-way trailer connector, like part # PK11720 for a 7-pole or part # HM40920 for the more common 7-blade. This way you can still run whatever is connected to that circuit without the truck running. However, it's going to pull power from the truck's battery and will eventually drain it. You can install a battery isolation solenoid, like part # PK5231201, so that the 12 volt auxillary pin will be switched off wioth the truck's ignition.
    view full answer...
  • Do Pollak 7-Way Round Pin connectors fit Together
    Yes, part # PK11700 and part # PK11720 do fit together. The PK11720 is the vehicle side connector and the PK11700 is the trailer side connector.
    view full answer...
  • Rubber Boot For Wire Protection On Pollak Trailer Wiring Socket - Vehicle End, # PK11720,
    Yes we do sell a rubber socket boot for the Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End, # PK11720. The product is Pollak 7-Pole Rubber Socket Boot, # PK11761, that fits over the back of the socket. Our website is not showing a picture right now so I will send you a separate email with a picture of the rubber boot.
    view full answer...
  • Running Lights Blinking When Trailers Are Connected Without Turning Lights on in Vehicle
    Thank you for the additional information via email. Since this issue is occurring on multiple trailers connected to the same vehicle, it would be most likely that the issue is caused by the wiring or harness on your tow vehicle. I would first check the 7 way connector for any rust, corrosion or dirt; clean off or replace as necessary. You'll next want to check the ground connection on your 7 way connector to make sure that it is secured firmly to a rust, paint and debris free surface on...
    view full answer...
    Image 1 for
  • Trailer Tail Lights Go Out With Headlights On And When Brake Pedal is Pressed On 1993 Chevy 3500
    It sounds like you have a ground problem on the trailer. However, there also could be a problem on your tow vehicle. We can isolate the problem to narrow the search a bit. Disconnect the trailer from the truck. Using a circuit tester, like part # PTW2993, test the 4-Way connector. Clip the tester to the truck frame as your ground, and test the brown, yellow and green wires to make sure they function properly. Brown is tail lights, yellow is left turn and brake, and green is right turn...
    view full answer...
  • Are there Round or Blade Pins in the 4-Way to 7-Way Trailer Connector Adapter # 37185
    The 4-Pole to 7 and 4-Pole adapter # 37185 uses blade style pins. I have included a picture for you to view. If you need to install a 7-Way round pin vehicle side connector you can use # PK11720. You will need to hardwire the wires to the back. You will also need rubber boot # PK11761 and mounting bracket # PK11771. Or you could install the 37185 and use an adapter to go from the 7-Way blade to a 7-Way round pin, # 47595.
    view full answer...
    Image 1 for
  • Where Are the Brake Controller Install Wires for a 2008 Chevy Silverado
    Sounds like the guy who you had install the brake controller may have been in over his head (no disrespect). But we can help! Your new body style 2008 Chevy Silverado did come with wires under the dash for wiring up a brake controller. If there were some that didn't we would have at least heard of one since we sell controllers for your truck all the time. To see how it would install check out the install video I attached. The wires are right under the dash near the brake pedal. That being...
    view full answer...
  • Trailer 7-Way Connectors and Brake Controller For a 2009 Sterling 7500 Series Dump Truck
    With the Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket # PK11720 it does not have a pin for a trailer brake controller as the commercial/agricultural trailers it connects to will tie into the air brakes on the truck. If you converted the auxiliary pin to use as a brake control wire you would still need to add a charge line circuit wire to maintain the breakaway battery on the trailer. Switching to the Hopkins Endurance Multi-Tow 7-, 5- and 4-Way Flat Trailer Connector # HM48470...
    view full answer...
  • How to Make 7-way to 6-Way Adapter for Semi Truck to Gooseneck
    Your semi-truck is going to have separate turn signals from the stop lights and your gooseneck trailer is going to have combined turn signals and stop lights. This means you would have to build an adapter that has a signal light converter so that your trailer can be towed with your truck. You would need to start with a 7-way male connector part # PK11893 to plug into your semi truck. For wiring you would then want the part # DW04914-1 sold by the foot. Then for the signal converter you...
    view full answer...
    Image 1 for Image 2 for
  • How to Connect Lance Trailer 7-Way Wiring to Truck with 7-Pole Socket
    Lance sometimes uses their own special connector (for whatever reason) so since your truck has a Pollak 7-pole like part # PK11720, I recommend cutting off the OEM Lance connector and installing a more common 7-pole like the Pollak # PK11700 that will match what's on your truck.
    view full answer...
  • Wiring Diagram for 7-Way Round Pin Trailer and Vehicle Side Connectors
    I have added a photo detailing the wiring connections for the Pollack Heavy-Duty, 7-Pole, Round Pin conncetor, # PK11700, see link. This is a SAE J560 compliant connector. The wiring diagram for the vehicle side connector, # PK11720, is pictured also.
    view full answer...
    Image 1 for
  • Wiring Diagram for a 1997 Peterbilt Semi Tractor with 7-Pin Round Connector
    The wiring color codes and wire gauge recommendations for the Pollak Heavy-Duty, 7-Pole, Round Pin, Trailer Wiring Connector, item # PK11700, are listed below. White - Ground Return - 8 gauge Black - Clearance, Side Marker, Identification - 12 gauge Yellow - Left Turn and Hazard Signal - 12 gauge Red - Stop Lamps and Anti-Lock Devices - 10 gauge Green - Right Turn and Hazard Signal - 12 gauge Brown - Tail, Rear Clearance, Marker and License-Plate Lamps - 12 gauge Blue - Auxiliary Circuit/ABS...
    view full answer...
    Image 1 for Image 2 for
  • How to Make a 5-Way Round Pin to 7-Way Round Pin Trailer Connector Adapter
    A 5-Way Round to 7-Way Round trailer adapter is not available, but I can tell you how to make one and what you will need. If the 5-Way round is on the vehicle, you will need the following: 5-Pole, Round Pin Trailer Wiring Connector, # PK11501 7-Pole, Round Pin Trailer Wiring Socket, # PK11720 7-Pole Rubber Socket Boot, # PK11761 Jacketed 6 Wire - per foot, # DW04906-1 (get 2 feet worth) Start by testing the functions of the 5-Way with a circuit tester, # PTW2993 if needed. Once you know...
    view full answer...
  • Wire Color for Brake Stop Lamp Switch Cold Side on 2006 Chevy Silverado
    You'll be looking for a white wire coming off the brake stoplight switch located at the top of the brake pedal. However, you don't actually need to do that, the 2006 Silverado actually has a connector under the dash in the junction box behind the emergency brake pedal as shown in the provided photo that lets you directly plug in the controller. Once the black cover of the junction box is removed, plug the harness into the second from the left slot in the top row. For a Tekonsha brake...
    view full answer...
    Image 1 for
  • Brake Light Switch Wire For A 2015 Chevy Silverado 3500
    The wire for the cold side of the brake light switch on your 2015 Chevy Silverado 3500 isn't useable so you'll need to install the Roadmaster Stop Light Switch Kit # RM-751463 so that you can simulate the signal for your Brake Buddy Stealth # HM39530 installation.
    view full answer...
  • Replacement Trailer Connector For 1995 Ford F-150
    I am not sure if you need the replacement connector for the vehicle side of your 1995 Ford F-150 or if you need the trailer connector that would plug into the F-150, so I will give you some options for both of them. You can use a circuit tester like part # PTW2993 to check the wires by function when installing a connector. If the connector you need is on the vehicle side and you determine it is a 6-way, I recommend part # PK12720. This is a plastic 6-pole round pin socket that would be...
    view full answer...
  • Finding the Cold Side of Brake Switch on Jeep
    The only way to find the cold side of the brake switch wire on your 2011 Jeep Liberty would be to use a circuit tester such as # PTW2993 and find the wire that only has power when the brake pedal is depressed.
    view full answer...
  • 7-Way Round to 7-Way Flat Adapter Recommendation
    If your vehicle has a 7-way round connector like a Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket # PK11720 then you could use a Trailer Connector Adapter # HM47425 to allow you to tow a trailer with a flat 7-way connector. I also attached an FAQ article on wiring for you to check out also. I would recommend you test the 7-way on your semi and determine if the 7-way has separate or combined tail light circuits. If you have separate circuits on the trailer connector you would need...
    view full answer...

< Previous
123. . .6

Do you have a question about this Trailer Wiring?

Info for this part was:

Employee Jackie C
Expert Research:
Jackie C
Employee Mike L
Expert Research:
Mike L
Employee Michael H
Expert Research:
Michael H
Employee Jeff D
Expert Research:
Jeff D
Employee Reno H
Expert Research:
Reno H
Employee Jameson C
Expert Research:
Jameson C
Employee John H
Expert Research:
John H
Employee Adam R
Expert Research:
Adam R
Employee Rachael H
Expert Research:
Rachael H
Employee Jeffrey L
Expert Research:
Jeffrey L
Employee Tyler C
Written by:
Tyler C
Employee Cole B
Installed by:
Cole B

At we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.