It is 6V packing developed as a principal use for the receiver of the engine car.
The cell adopts Intellect 2000(AAA), and can surely make the servo and the receiver work by a high-powered output.
The row of the cell is a straw bag type of 2-2-1, and it is the best for the car of MUGEN.
Intellect 2000 Packing for 6V 2-2-1 straw bag type receiver (five cells)
Source : Team Trion