These are your standard 1.5V AA alkaline batteries from Panasonic. Don't even think about trying to recharge these. Roughly 1500mAh per AA cell. Combine 4 to get ~6V peak, and ~4.8V as they hit their discharge curve.
Sold in single units. But if you order four at a time, it makes it easy for us to package them.
Note: This item is non-returnable. If this item arrives damaged or is not functioning properly, please do not hesitate to contact us to see if further actions may be taken.
Documents:
Datasheet