[Al Skierkiewicz]

I have not seen any significant differences. Most batteries are made by a small number of manufactures. The size we use allows only so much lead, fiberglass and plastic in the volume. That is why all 18 amp hr. batteries are the same size. You will find different ratings among different manufacturers, but if you examine them closely, the data is more massaged by marketing people to make their battery sound better for a given market. That being said, off brand batteries may have taken significant short cuts in manufacturing and may not meet specifications of the name brands. We had two batteries of the same local manufacture in Australia, fail while charging at that regional using a known good charger.