AT&T 75 Wiring Manual page 291

110-TYPE HARDWARE
SYSTEM TRUNK AND TIE TRUNK PORT LABELS
WP-90929, List 1 or 3 concentrator cables can be used between the switch cabinet and the
110-type terminal blocks. The label shown in Figure 2-53 is used to identify 3-pair trunk
circuits from the switch cabinet. The label shown in Figure 2-54 is used to identify 3-pair tie
trunk circuits from the switch cabinet.
Figure 3-53. System Trunk Port Circuit Labels
3-75