I use a 7pin on a 1000lb trailer. It still has brakes and I charge my battery off of the tow vehicle. I'm glad it comes with a 7 pin. You can easily convert a 7pin to a 4pin but not the other way around.I agree this all doesn't add up. If it's limited to 3500lbs why not a Class 2 and 4-pin connector?
Sponsored