I used two 4,2-3,6V LithiumIon batteries (In series for 8,4 - 7,2V) , I suggest using these instead: http://dx.com/p/18650-rechargeable-lithium-lifepo4-battery-1350mah-5105 *NOT They are 3,6-3,2V, so they fit better with the Diodes 3,4 - 3.2

EDIT: Gone from using 2 to using 4. The holsters can no longer fit inside the tube, so I used another type of batteries called CR123A

http://dx.com/p/ultrafire-3-6v-880mah-lc-16340-protected-cr123a-battery-2-pack-3273

This makes the setup= -3.6V-3.6V-3.6V-3.6V- (14.4V total)