Probably go for detachable. Whats the difference between 12 and 13 pin ?

Electrics wise, it really depends on what you are towing. Most modern caravans come with a 13pin plug, this contains all of the electrics for the van incl charging, fridge and road lights in the one plug. you have one small black socket on the car

Older caravans and trailers use the 7n and 7s systems, two plugs, one white and one black on the car, one for the road lights and one for the onboard charging systems etc. Personally, having had both on different vans and trailers, the 13 pin solution is best with a positive lock connection and less obvious on the car.

there are various adaptors so you can use older stuff with the new type of plug, and newer stuff with the old type etc. or you could easily swap the plugs over on trailers/caravans and combine the 12n and 12s wiring into one 13 pin plug.(diy for £5)

[urlhttp://www.pfjones.co.uk/range-rover-2005-detachable-tow-bar.html#.UQGl46VBDEl[/url] for 2005> detachable, with no wiring kit. As Nbunney says it is do-able on your drive with a decent socket set and the wiring is plug in (i think coding is a mater of debate, some say it does and some say not. I think that the functions work but there are some TC issues which need the coding ) There is nothing that can't be fixed with a hammer😜😜
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