What batteries should I get for my visual or audible altimeters?

ALWAYS! Get the type and size of batteries that are recommended by the manufacturer to ensure your unit works and performs properly.

L&B Altimeters are well known for having a great battery life when the correct batteries are installed on your unit.

You can find these at the link below:
https://www.chutingstar.com/skydive/altimeters/batteries-and-chargers?manufacturer=Larsen+and+Brusgaard