Skid plate

A skid plate is an abrasion-resistant material affixed to the underside of a vehicle or boat to prevent damage to the underside when contact is made with the ground. 
Skid plates may be used on off-road vehicles, motorcycles and lowered vehicles to prevent damage to the underside. Fake skid plates are also added to vehicles for an off-road look.
Steel skid plate for the protection of the engine and the gearbox.
The advantages: