What is the Difference between an H6 & H7 Battery?

Now that OPTIMA has both an H6 (also known as a Group 48) and an H7 battery (also known as a 94R), we are finding some folks have trouble telling the two apart. By themselves, they look nearly identical and even when they are next to each other, the differences may be difficult to see. While the handles on the OPTIMA batteries make it easier to tell them apart, not all batteries have those handles. 

Many batteries from the factory do not show the size on the label or any indication of what size the battery might be. Instead, it may show a series of part numbers that may make sense to that automaker, but won't make sense to you when you are trying to replace it. The length of these two batteries and/or the distance in between the terminals may be the easiest way to tell these two batteries apart.

The DH6 YELLOWTOP measures about 9 1/4 inches from the outside edge of one terminal to the other, while the DH7 YELLOWTOP measures about 10 1/2 inches. If your battery terminals are more than 10.5 inches apart, then you may have an H8 battery. It's important that you know which battery is in your vehicle, because the hold downs that keep these batteries securely-mounted in the vehicle are probably unique to those sizes.

In conclusion, the H6 and H7 battery may be similar, but they are definitely not the same battery.