only Coupling Joints: Nitto decided to reinforce the coupling joints in the Terra Grappler G2, which connects the outer most tread blocks to the center blocks, to increase the block edge rigidity. Full Depth Sipes: Terra Grappler G2 is equipped with full depth siping. Not only do the full depth sipes offer a functional benefit, it helps maintain the appearance of the tread design as the tire wears. Shoulder Lugs: The staggered shoulder lugs on the Terra Grappler G2 provides additional biting edges in off-road conditions. Further more, the new sidewall designs conn.