This read-write DisplayString states the low-frequency range that the duplexor passes through without attenuation; frequencies outside that range are attenuated enough that the RF resource using this duplexor cannot transmit or receive on them. It tells an admin which lower-band frequencies are actually usable with the currently installed duplexor hardware, which matters when planning channel assignments. For example, before configuring cwrTxFrequency to a frequency in the low band, an admin checks cwrDuplexorLoPassbandRange to confirm that frequency falls inside the duplexor's usable low passband.