Special Lead Alloy Grids - Reduces Self Discharge Factory Activated - Filled, Sealed and charged at the factory. Sealed Design - Eliminates Acid Spilling Maintenance free technology - Eliminates the need to check and Refill the battery. Absorbent Glass Mat separators - Lowers internal resistance for faster recharging and higher performance. Compressed Plate Packs - Protects against damage due to vibration. Flexible mounting angle - Supports multiple fitment angle in the vehicle.