English Art/Literary Other

‘Last year the combined workshops (or “pinneries”) of Ankh-Morpork turned out twenty seven million, eight hundred and eighty thousand,nine hundred and seventy-eight pins,’ said Stanley, staring into a pin-filled private universe. ‘That includes wax-headed, steels, brassers, silver-headed (and full silver), extra large, machine- and handmade, *reflexed* and novelty, but not lapel pins which should not be grouped with the true pins at all since they are technically known as “sports” or “blazons”, sir—’
--quoted from Going Postal (2004, fantasy fiction) by Terry Pratchett (link: https://www.google.com/search?tbm=bks&q=“reflexed and novelt...

Stanley is a pin collect. What is "reflexed (pin)"?
Thank you!