What size battery pack did you use?

I wondered if I might go up a bit from 7.2v.


Soldered some wires on the board I am going to put into boat but what confused me is:-

This is on the Tiger.

Neg and positive enter bodyshell. Neg goes to the control board. Positive goes to on/off switch, but there are three wires on the switch. One red positive from battery, one red out to board and another RED out which is connected to the NEGATIVE on the board.
A more knowledgeable person said it is a single throw double pole switch (I think) ,but he couldnt figure out why it is wired like that and he designs and makes his own PCB's. He said it must be for a reason but as he's not into R/C he wasnt sure.

I connected my new board to battery by sticking wires into plug, connected multiplug to tiger and everything worked OK.