This read-only object indicates which of the duplexer's two passbands, low or high, the RF resource is currently using to receive transmissions. Because the desc notes the RF resource can receive on either passband, this setting tells the admin which set of frequency boundaries (the Lo or Hi passband min/max objects) is actually relevant to the link's current receive path. For example, if received signal levels look wrong, the admin reads this object to know whether to compare the receive frequency against the low-passband or the high-passband limits.