The last thing anyone on the trail wants to deal with is gas tank that has lost a battle with a rock. With such a critical component to your Jeep when off-roading, its very important to make sure that these are protected! The RockHard 4x4 design is completely bolt on. Each steel skid plate is 3/16" thick and Aluminum is 1/4" thick. Each Skid Plate comes with a "Rock Dome" bolt design to countersink the bolt heads so that they wont be damaged either! These Skid plates can be used by themselves or interlocked with other RockHard 4x4 Skid plates and are backed by a lifetime warranty!