I found a nice advertisement from Harley Davidson advertising their new Hydra Glide front forks in a 1949 magazine. In that same issue I found this 1949 Exide battery advertisement. This ad was created when motorcycles, cars and trucks had a 6 volt electrical systems instead of 12 volt. On most wet batteries you can tell how many volts it is by the number of caps at the top, approximately 2 volts for each cap. You can see this 6 volt Exide battery has 3 caps instead of 6 for pouring in the initial sulfuric acid to activate the battery, and for adding distilled water for maintenance. The Exide company is still in business today.
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