ATM DIAL T.4213
British Post Office standard. Brass base with two positioning and one tapped lug for mounting. Black finish. Black figures on white ground “1 - 0.” Instruction card protected by transparent disc. Two-make shunt spring combination (a). Impulsing contacts, silver ; shunt contacts, silver. Can be supplied both numbered and lettered for use in Director areas (T4214).
Taken from the 1951 ATM Catalogue
Last revised: October 06, 2012