The OTR Group Size 31S Gold Anchor Bonded Heavy Duty Truck Battery ensures Expertise Built In™, being built for power from the inside out and boasting state-of-the-art-grids that are calcium/ lead alloy punched. This provides maintenance-free performance, consistent power, and enhanced durability. Furthermore, the anchor bonding “anchors” the plates to the bottom of the container, which improves protection against vibrations and bumps in the road. OTR knows what it takes to repair and maintain Class 6-8 trucks, so they deliver solutions, making your job easier and more efficient. OTR warranties are comparable to or better than OE and top brands. All heavy duty truck parts offer the same form, function, and fit as the OE replacement parts. FleetPride is your First Click in Heavy Duty®.