On 8 September 1967, the electronic portion of Dyemarker was divided and the aerial, sensor-based portion was designated Muscle Shoals. On 1 June 1968, the aerial portion was redesignated Igloo White. That name became the most associated with the program though various elements received a number of separate codenames. All resources for Dyemarker/Muscle Shoals were redesignated Duck Blind in April 1968, and in June 1968 Muscle Shoals outright became Duel Blade. In October 1968 Duck Blind was changed to Duffel Bag.
