STERLING TELEPHONE AND ELECTRIC Co. Ltd
STERLING "PRIMAX" SYSTEM OF AUTOMATIC INTERPHONES
ALL LOCAL BATTERIES ARE ENTIRELY DISPENSED WITH
No. U 412
Similar in all respects to U 410, except that a Standard Hand Combination No. U 170 is fitted instead of separate Receiver and Transmitter.
NOTE: The Switch Contacts and Line Terminals are fitted at the back of the Instrument, and are well protected from dust and rough handling. To facilitate Wiring, the Instrument is provided with a Hinged Fixing Batten which gives easy access to the back for connecting the Lines or inspecting same.
For 5, 10, 15 or 20 Lines.
Instruments for over 20 Lines are made only to order.
NOTE: We are still prepared to supply Instruments for extensions to existing installations which are fitted with ordinary Central Battery or local Speaking Batteries, if stipulated at the time of ordering.
Taken from the Sterling Catalogue No. 11 & 12
Last revised: April 28, 2021