Polycom SpectraLink RCO400 - Manual (Page 37)

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PN: 1725-36122-001_N.doc 37
Connect demarc block 25-pair cable
In some installations the demarc block is connected to the Interface
Module using a 25-pair Telco cable with one male and one female RJ-
21 connector. The female connector is plugged into the right side of
each cross-connect block. The male connector from each cable will be
connected later to the front of the Interface Module.
Be sure to use only cables that are UL-listed communications circuit
accessories. Only 24 of the 25 pairs are used in the Interface
Module cable.