https://www.ebay.co.uk/itm/2x-Ultra-light-Bike-C-Brake-Pad-Road-Folding-Bicycle-Extend-Caliper-Brake-Block-/164553007479 might be a more / less safe option
that thing, and filing on brakes sounds like a deathtrap or deathtrapdem.
@doubleodavey started
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https://www.ebay.co.uk/itm/2x-Ultra-light-Bike-C-Brake-Pad-Road-Folding-Bicycle-Extend-Caliper-Brake-Block-/164553007479 might be a more / less safe option