The car has a flat underbody and a rear diffuser for improved downforce. The 599 utilises an underbody spoiler and venturi tunnels that contribute to downforce. The car lacks any front or rear wings - downforce comes from the underbody. Other exterior changes include underbody diffusers and the rear diffuser shared with the 488 GTE. An underbody rear fin helps stabilize the vehicle at higher speeds. Four-wheel electronic traction control is standard and off-road underbody skid plate armor is optional. The diffuser "drives" the underbody, which produces the downforce. The aft part of a car underbody is where a rear diffuser is usually located. The stainless-steel panels are fixed to a fiberglass underbody. Saab's trademark underbody mounted "snow & gravel flaps". The smooth underbody ensures that the airflow is not interrupted. The vehicle had an improved V-hull to protect from underbody blasts. Starting with vehicle bodies manufactured , all units were outfitted with a triple underbody shield. One area in particular attracted their attention&colon; the underbody airflow. There is some underbody armor that moderately protects against mines and roadside bombs.