DIY. It's as simple as plug n play.
https://www.amazon.com/4-pin-7-trail...railer+adapter
OR rewire. if you can disassemble your guns for cleaning. This should be easy.
https://autocardesign.org/4-pin-to-7...iring-diagram/
great-kazoo just saved you $100.
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"when you're happy you enjoy the melody but, when you're broken you understand the lyrics".
Trailer brakes to haul an atv seems like overkill but to each their own.
I?m guessing the tow vehicle is something smaller than a half ton truck?
Seems most half ton and larger trucks have come standard with the larger plugs for years now.
The Great Kazoo's Feedback
"when you're happy you enjoy the melody but, when you're broken you understand the lyrics".
Most ATV trailers will not have brakes unless it is a 4+ place trailer.
You will need a brake controller of some sort.
To be honest though, if you're pulling something big enough to need brakes, you need a bigger tow vehicle
Edit: you beat me to the post on the brake controller. Should be fairly easy to wire up.
You're gonna have to squeeze those on there pretty tight. Sounds like just barely enough trailer, depending on the SXS
7 pin isn't that hard to wire in. You will just need to add the +12v to charge the trailer in your situation. Trailer likely doesn't have reverse lights, and that Curt deal will provide the brake signal.