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Viper 7961NC is a Viper Mark II piloted by Louanne "Kat" Katraine that survives the Battle for the Tylium Asteroid (TRS: "The Hand of God").
She later pilots it during the events revolving around the initial events with the Pegasus. ("Pegasus" "Resurrection Ship, Part I")
A Viper Mark VII is later seen with the same markings (TRS: "Exodus, Part II"), and is apparently still in service well after the Battle of New Caprica (TRS: "Crossroads, Part II").