Hi to Howard and ChrissyLizzie
My Name is Keith and I along with my wife own Pro-tec Covers.
We are as you see a family firm and also caravaners, our products and customer care are very important to us.
The problem with the dark marks are still a mystery to us and our fabric manufacturer. We have had 9 instances of this, 4 were down to the covers being used on caravans with dull and faded paintwork, the cover had polished the caravan and in each case the customer had thought that the dark dull bits were caused by the cover, when in fact it was the other way round. This was remedied by t-cutting and polishing.
Our fabric is manufactured in the UK to a very high standard, out of each roll of 250meters of fabric we can get approx 12 covers, so logicaly we thought if there was a problem with the fabric the other customers with covers from the same roll would have the same problem, we contacted them, and all were fine.
We are still trying to find a likely cause, even though out of the 2,000+ covers we produce every year, 5 is a very small percentage.
We have asked questions like what surface is your caravan parked on, what polish did you use, is the area dusty etc but as yet haven't found a common reason for the marks.
Pro-Tec Covers will have been selling covers for 10 years next year, we have used our covers all that time with no problems but more importantly 43% of all orders we now take are from existing satisfied customers.
If any one would like to contact me they are more than welcome.
Regards Keith