What is the battery life? Can I use rechargeable batteries to save money?
The battery life depends the amount of use and age of the battery. Normally you can expect at least one to two months, if not more. Remove the battery if the unit is not used for a longer period. Don’t use rechargeable batteries. The required optimum voltage is above 8 Volt and rechargeable batteries drop below this very rapidly. Also there is the danger of them exploding if they short-circuit.