[quote="Don Coffey"]
[quote="gmc15"]
13 pin.

All new vans come with 13 pin plugs now and they are better than 7 pin:-
Watertight fitting
Twist-lock coupling system removing the need to use force.
Single socket mounting - good for detachable towbar systems
Single plug on the caravan/trailer
[/quote]
+1 so much easier and secure than the seven plug, plus someone buying your car in the future will expect a 13 pin if they have a caravan.
Don
[/quote]
+2
They are far more reliable and less prone to dicky connections...
Only issue is if you need to tow someone elses trainler with 7 pin then you need the adaptor..
Conversely when your X is off the road (or stood on teh side of oone waiting for a lorry!!) and you borrow another vehicle which has 7pin sockets you need another adaptor... Guess how i found that one out!!!

If things were meant to be easy, then I will soon complicate them....
Please note...
Anything I say is only from my personal experience and knowledge..
I don't assume to know everything, and know there is a lot I don't know..
But then I could be talking bollox.. O:-)