Just had a close look at the meter, there is a battery symbol on the top with Lithium written inside and a label saying 433MHz, so I am assuming the battery is rechargeable probably from the flow of water on a mini turbine. The meter is presumably the sort that can be read by a drive by. At the moment I cannot see how to access the innards it will not unscrew off the body and there is no visible battery compartment, makes you wonder about longevity of the battery and how often the battery/meter needs replacing, we have been here in September 7 years and nobody has ever read the meter in that time.

Richard