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Bloody hell - 6 tubes will get you another pair of boots (if you like me a n Scottish & buy 2nd hand - but near new)

I also heard it rotted stitching - but to be honest - and I use my boots (vary between 3 boots depending on if I climbing trees or Quading or just hauling arse) 3-5 days per week and had not...

I use Kiwi Dubbin
Not sure if its the right thing to do - but I do know manufactures will try as hard as they can to swing you into their own products
Dubbin from Supermarket is cheap and a tin...