I have collected a few of these over my 18 months of collecting. I have sorted them in rows by rarity IMO. Top line very rare, second line somewhat rare and bottom line not very rare at all.

Be interested if anyone has any information on these and in particular how old they would (short of Victorian and Scottish for most of them). Also interested in what the more complex ones would be used for as I assume they would be for more important access? The T shapes one also interests me as this is quite iconic.

does anyone have some pictures of some super rare ones?

thanks Simon

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