MillerTech (AGM) Batteries are designed to be deeply discharged and recharged hundreds of times. They are designed and built differently than traditional flooded batteries. MillerTech AGM Batteries are sealed lead-acid batteries made with Absorbed Glass Mat (AGM) technology. The electrolyte is absorbed into the fiber separator material rather than in free-flowing liquid form. They use more lead, heavier plates, and other proprietary materials that enable them to deliver more power and capacity over many life cycles.