LINE-X is an excellent solution for adding a permanent undercoating to you car or truck.  The only drawback is we can’t apply it unless your vehicle body is on a rotisserie.  The reason being is the way LINE-X is applied it relies on gravity for the texture coat.   Further,  assembled vehicles have exhaust, wires, cabling, brackets, and components which if coated with LINE-X would make it impossible to remove and replace.