This applies the same CLP-1-first selective discard logic to the ABR/UBR queues, the lowest-priority traffic class on this card. Because ABR/UBR traffic is the lowest-priority, most loss-tolerant class on this platform, this threshold is typically the most permissive of the whole family; an admin lets this queue build up further than any of the CBR or VBR queues before even discard-eligible cells start getting shed. For example, cardClp0UAbrThreshold is deliberately configured as the highest, most permissive threshold among the CLP0 family on a given card, reflecting ABR/UBR's position as the traffic class expected to absorb congestion first and most.