21mm [1 farthing, 1 penny] Farthing after 1859. 18mm [5 pecne, 1/2 penny - small]. 18mm /19mm /20mm /21mm /22mm /23mm /24mm /25mm /26mm /28mm /30mm /. It's very useful to protect your coins. 32mm [1 penny - big, 50p old - big].
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