ACDelco 47AGM Professional AGM Automotive BCI Group 47 Battery High density negative paste, improves performance and increases battery life;Terminal Type: Top Post Enhanced life alloy/Silver Calcium stamped alloy increases cycle life and improves performance Calcium Lead positive grid, maximizes conductivity and allows for low resistance Robust Envelope Separator with puncture-resistant back, allows for increased acid circulation and prevents shorts. Improved acid circulation, helps the battery to remain cool, and extend battery life. Vent cap design that resists acid leakage Precision manufactured ribbed case that is 100% pressure tested, helps avoid future leaks and adds strength and rigidity 100% Electrical short tested to minimize early failures