Rain TBD User Manual page 18

RAIN S.p.A. via Kennedy 38/40
20023 Cerro Maggiore ITALY (MI)
3. BATTERY INSTALLATION
Unscrew the cap on the back of controller and install
two AA type 1.5V batteries, taking care to follow the
correct polarity.
NOTE: before closing the compartment, make sure
the battery compartment is properly clean.