Product information:

For protection of 4-wire leased line modems.

Pins Protected: Pins 3, 4, 5, 6 on the RJ-45
Interface; (RJ-11 Pins 2, 3, 4, 5 via 6 in./15 cm
patch cable)
Protection Mode: All pins Common Mode to shielding Protection Mode: All pins Common Mode to shielding
braid; Differential 3 and 6, 4 and 5.