This unit is generally NOT supplied with a battery for the remote. A CR2032 button cell is required.
Embarrassingly petty and reason enough not to buy. A pity.

Thanks - wanted to buy. But without a battery? That's ridiculousness personified.

Mine didn't come with a battery either - very weak!!! Once again they save 50 centimes, which adds up over all the sold copies and thus a great manager collects another bonus because he could save a little and make more profit....

I didn't have a battery with me either.

Actually, a battery is rarely included. Or have you ever bought a toy in which the battery was already included?