Huw Eastwood wroteGary IIRC Brian wrote a short detailed article that covered those in Keyways a year or so ago.
This lock is also illustrated in Tony Beck’s Lock Collector Issue 19 as No.47313, a two-stump wedge bolt lock with incredibly close gate. The B B on the block could refer to Branch Bank Safe which was triple locked.
Numbers 47000 were made in 1928, just like me.
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