x3 on the Tekonsha brake controller, mine is fitted just in front of where my right knee sits. There is a thread I started about wiring it up if you search, you have to take the trigger feed direct from the bulb area, not the brake light switch.
My trailer probably goes no more than 1000kg`s when loaded. I dont even notice its there most of the time, its only on long hills that the car changes down earlier but no loss of speed.
https://www.aulro.com/afvb/images/im...013/08/761.jpg

