AGM batteries are not hazmat. I don't normally necropost but AGM batteries along with tool, laptop, and device batteries are all considered shippable by the USPS.
However, 3 batteries max for lithium ion batteries which means legally people cannot ship to the buyers in flat rate boxes. UPS has no notes for lithium ion batteries except that they can only be shipped domestic ground.
AGM batteries need only be marked "Non Spillable Batteries" and there is no limit. I for on encourage attempts at battery reviving, reason is, most AGM batteries do not produce sediment, and with the proper digital charger, most will come back after a few cycles to about 80% original capacity so long as they aren't cracked and they haven't been dropped.
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