Adding Electric Brakes to 7x20ft trailer??!!?

that size trailer should already be equipped with brake assemblies on each wheel. You will need to purchase an actuator to mount inside you vehicle to make them work. Do the job by the instructions and do not take advice of folks the say they pull trailers without brakes. This can be done but it drastically reduces your stopping distance and adds severe load to your vehicle brakes, not to mention the safety hazard to the rest of us on the road. Properly installed trailer brake mechanisms will provide you with stopping stability and reduce the wear on your vehicle brakes. I have 2 million miles on the road and have seen dozens of ACCIDENTS from poorly maintained trailers.

Definition of ACCIDENT - consequences of decisions made by idiots.

az-tex . i have an 1800 lb trailer ,it has brakes but i dont use them.i haul up to 7000 lbs and its rated at 10,400 lbs. it dumps .i have all the wire ran except under the dash tween the pedal and the brake box.its just an extra expense.