Will you horn experts tell me which model I have?
You have a “type c” Lucas hf1234 (flat bezel, rippled tone disc, tone adjuster screw on the back). Urban myth has it that their should not be “Altette” stamped on the bezel but where the rivet counters get that info I don’t know
Note the “type a/b/c” is not as far as I know a Lucas descriptor, just an indication of what year they were made, as the design of the Altette changed through the years. Type c is thought to be circa 1953 onwards.