Special Features:

Fwire line 4, wire telephone set 1, talk battery 1, lamp flash circuit 1, incoming ring timing 1, e and m lead control 1, ring interruption circuit 1, hold feature 1, audible ringback tone to calling par type 1

Properties:

Two or more different types of items having a common mounting or mounted on each other which together form a portion of a telephone terminal but which in itself is not a complete functioning item and cannot be assigned a more definite item name.