AEG Protect A. 1000 Operating Instructions Manual page 13

When replacing the batteries, the following must be observed:
Only ever use identical, maintenance-free sealed lead
batteries with the same data as the original batteries.
Danger! Explosive!
Never throw batteries into open fire. Never open
or damage batteries. (Electrolyte may leak out
and damage skin and eyes. It may be toxic!)
Batteries can cause electric shocks and high
short-circuit currents.
Therefore, take the following safety precautions when working
with batteries:
♦ Take off watches, rings and other metallic objects!
♦ Only use tools with insulated handles!
For personal safety reasons, never switch on the
main switch when the mains connector of
PROTECT A. is disconnected!
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