LOCKS No's 29A & 29B
Used on Telephone No's 706 and 710 to stop outgoing dialled calls.  Emergency calls to 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.

The keys are all different.

Introduced circa 1964.

Diagram - N859.

Drawings - 63325 and 91681.
 

Lock in situ

Template in position ready for the two holes to be drilled
 

 
 
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Last revised: January 18, 2023

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