Automotive Battery Terminals
Automotive batteries typically have one of three types of terminals. In past years, the most common design was the SAE Post, consisting of two lead posts in the shape of truncated cones, positioned on the top of the battery, with slightly different diameters to ensure correct electrical polarity.
The "JIS" type is similar to the SAE but smaller, once again positive is larger than negative but both are smaller than their SAE counterparts. Most older Japanese cars were fitted with JIS terminals. You must ensure that when you are buying a new battery that you know which terminals you have. One must also look at the orientation of and which side of the old battery the terminals are on, otherwise you might find that if the terminals are oppositely oriented that the battery cables will not reach the new battery terminals.
General Motors, and other automobile manufacturers, have also begun using side-post battery terminals, which consist of two recessed female 3/8" threads into which bolts or various battery terminal adapters are to be attached. These side posts are of the same size and do not prevent incorrect polarity connections.
L terminals consist of an L-shaped post with a bolt hole through the vertical side. These are used on some European cars, motorcycles, lawn and garden devices, snowmobiles, and other light duty vehicles.
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