Can I use 14500 to replace 2x AA battery?

[lipo99]

I ordered some overspec ebay laser pointer.

Someone suggested to use 10440 battery to increase output. However, I have some 14500 battery lying around at home.

1) Can I use 14500 to power instead of 10440?
2) If I can use 1x 14500, do I buy this dummy AA to fill up the space?

 

[Blord]

1) the voltage is the same so both are usable if the laser can fit the larger 14500 cell.
2) you can use any dummy you like as long it fits.