This object holds the list of specific DS0 timeslots on the parent DS1 line that are bundled together to form this logical serial interface, and like the DS1 index, can only be set at bundle creation. This determines the actual bandwidth of the bundle, since combining, say, 12 timeslots gets a roughly 768kbps circuit, so getting this channel map right is what defines the bundle's capacity and which physical timeslots must not be reused elsewhere on the same T1. An admin provisioning a 4-timeslot, 256kbps fractional T1 circuit would set this object to the specific 4 timeslot numbers reserved for that circuit, leaving the remaining timeslots on the T1 available for other bundles or channels.