4S2P will fit in there. Actually, it's 4S1P X 2: one 4 cell pack per motor. I'd go with 5000 mAh 50C LIPOS. Stephen sells them here on OSE parts. Lots of other sources around. JIM
JIM MARCUM: NAMBA 777; EX? SoCal FE Racers Club; D-19; Official 2012 NAMBA FE Nationals Rescue Diver; Purple Heart Viet Nam Vet; Professional SCUBA/HOOKA Diver, KELCO, 1973-1978; BBA 1978, Magna Cum Laude; MBA 1980 w/honors; Retired DOD GS1102-12 Contract Specialist
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