Used with public Coin Collecting boxes on Telephones No. 115, 119 and 123.

Fitted to the cash box compartment cover and different keys were allocated to each lock.

These locks are similar to the Lock No. 6 which superseded them, the difference being was that the corners on the No. 4 were square whereas the No. 6 were rounded.


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Last revised: October 30, 2022