its a really good pump we have had ours ten years or more .Inside is a small sealed acid battery available from Ebay (the measurements have to be precise to fit,ours lasted 8 years).
our chargers wire broke right at the box so we use a 6v DC 500mA PSU (centre +) i had in the shed ,a 6V 1 amp etc would be fine so long as the connector fits the pump and the centre of the connector is positive
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.