AT&T 75 Wiring Manual page 314

110-TYPE HARDWARE
Figure 3-73. 258A and BR2580A Adapters
356A ADAPTER
The 356A adapter (Figure 3-74) plugs into a 25-pair female cable connector. The 356A
adapter divides the 25-pairs of leads on the cable into eight individual 3-pair circuits.
Although the circuits are 3-pair, the 356A adapter's modular jacks will accept an 8-pin
modular plug used on the 4-pair station cable. Remote powering is accomplished using a
400B2 adapter. (See ADJUNCT POWERING section for details.)
Caution: Adapters wired similarly to the 356A should not be used. Their jacks
will not accept 4-pair plugs.
3-98