The seat on my Humber is certainly knackered at seven years, I've just ordered a new one this weekend in fact. The material has gone brittle (probably due to UV exposure) and has cracked where the "wrinkles" would be when it is sat on. It looks like it was probably quite strong material when made - its quite thick - but the fabric integrity has just broken down and you can tear it with your finger.
I'm not a seat builder but will willingly accept a free sample and trial it under the ozone hole for you
A Boat is a hole in the water, surrounded by fibreglass, into which you throw money...
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