canvas cover waterproofer

+1 for Waterseal - a lot cheaper, seems to work at least as well and causes no damage although keep it off the gel as it does mark - albeit equally the marks polish off.
 
Bought a 5 litre can of fabsil from ebay ages ago, I just roll it on to the covers every year with a foam radiator roller, let it dry and you're good to go. It's pretty decent stuff and seems to last up to two seasons if required..
 
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