LOCKS No's 29A & 29B

Used on Telephone No's 706 and 710 to stop outgoing dialled calls.  999 can still be dialled.

The Lock is supplied separately and comes with two keys.  The lock worked in conjunction with a Dial No. 28, which replaced the original dial, and a Cord, Instrument No. 1/42 Brown 10.5".

Two holes are drilled in the telephone case and a template is supplied for this purpose.

The lock cannot be fitted to a telephone with a carrying handle.

Introduced circa 1964.

Diagram - N859.

Lock in situ

Template in position ready for the two holes to be drilled


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Last revised: May 16, 2022