I plan on flying Delta Airlines from NYC to St. Louis in a couple of weeks for a job assignment. Their latest published carry-on restrictions for Lithium-Ion batteries states "Lithium ion batteries not installed in a device (spares) must be in carry-on baggage and no more than two (2) spares between 100 and 160 watt hours are allowed." It mentions nothing about the number of Lithium Ion batteries LESS than 100 watt hrs you are allowed to carry. My case holds five 57.72 watt hour P2V+ batteries - each safely separated. I contacted the airline and the rep told me "that should be fine". I have no faith in the word "should". I will be calling again but was wondering if anyone here has carried a case through airport security and onto a Delta flight containing multiple Phantom batteries.