I've used many of these products over the years and most of them wash of at the slightest bit of rain but after going to the nationals last year and taking to people some one recommended this Autoglym so I tried it and I'm really impressed, my bumpers on the Mk1 are 37 years old and they are faded, the autoglym does a fab job at getting them nice a black and it sticks to the bumper very well and lasts a few washes/ rain showers. You also don't need to use a large amount and it's a gel so no water down liquid like in many other products out there so a bottle lasts a long time.
Cloth the put it on, leave it to dry for a short time and other cloth to buff it up.
I've tried various brands from back to black to Meguiars and the Autoglym stuff is the best so far.
Other places sell it as well so shop around.http://www.halfords.com/motoring/car-cl ... -gel-325ml
Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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