NATIONAL TELEPHONE COMPANY
BATTERY INTERCOMMUNICATION TELEPHONES
Pattern No. B510
Comprises - Hand Combination Transmitter and Receiver, Cord, Fixed Cradle, Induction Coil, Bell, Push Button and Line Selector.
The connections in this pattern instrument are all enclosed, but easily accessible without removing the instrument from the wall.
5, 10, 15, 20, 25 & 30 line models.
Last revised: July 07, 2020