C6

Counters is Mastercard's M/Chip concatenation of the card's offline risk counters and accumulators into a single field, related to the Lower and Upper Cumulative Offline Transaction Amount tags (CA and CB, both covered alongside it here) whose values C6 packages together for efficient transmission or storage rather than requiring each counter to travel as a separate tag. Being M/Chip-proprietary data rather than a core EMV tag, its exact internal byte layout, which specific counter occupies which position within the 10 bytes, lives in Mastercard's own M/Chip specification rather than in EMV Book 3, and this entry can honestly state that it exists and broadly what it aggregates without asserting a byte-by-byte decode this dictionary can't corroborate against that scheme documentation - consistent with the export's own verificar vigencia flag on this field's source citation. A terminal enforcing M/Chip's offline risk logic needs Mastercard's documentation to actually decompose C6 into its constituent counters; a generic EMV parser can only report that the field is present and how long it is. See Mastercard M/Chip 4 Card Application Specification.