Proper securing of hinges on a folder is pretty critical. Yet manufacturers can come up with something so ridiculous as aluminum bolts securing the hinges. In the case of Brompton I came across such a product (below) sold under Parsche brand. The bolts were additionally thinned at places to add some functionality. The product has since disappeared from the market, but from the description I fear that there are other offerings around with alu bolts for hinge clamps.
