Anyone know the size or type of batteries used in this
model? On the back 
Sure. It takes 3 off N size cells. These are 1.5V each. Whatever you do,
don't use the similar-sized 12V batteries (used, I believe in some car
alarm key fobs, etc) which will totally ruin the calculator.
N size cells are easy to obtain in the UK (even food supermarkets sell
them), but I am told they're harder to get elsewhere.
  cover it shows three batteries being used to power the
calculator. Thanks in
 advance
  
-tony