Thread: Has anyone made their own trailer?

In England I used a Ifor Williams branded trailer that was brillant, it had a braking system on it where you could reverse without getting out and flicking the override thingy over. It wasn't an electronic solenoid either. Unsure of how it worked but someone mentioned something about the brakes don't work when wheels are turning backwards. Anyone know of these systems? I want to put it on my next trailer.