Posted by Vic on 05/01/2023 12:47:27:
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The last of my good ones seem to be made of 0.15mm plastic.
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I think you will struggle to find anything in 150 micron these days
… the eco-warriors frown on such extravagance
Beware: some of the advertisers seem to be quoting ‘thickness’ as the double-film of a bag 
MichaelG.
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The Diving suppliers sound the best bet so far.
MichaelG.
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Edit: __ Transpack is a reputable UK supplier:
… but I note … this is what they are calling Heavy Duty
https://www.transpack.co.uk/grip-seal-bags-heavy-duty-5×8
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Another Edit: __ This style uses thicker film:
https://www.transpack.co.uk/red-zipped-wallet-370×255
Edited By Michael Gilligan on 05/01/2023 21:08:41