A self-propelle anti-tank gun, or tank destroyer, is a type of armoured fighting vehicle. Tank destroyers are used primarily to provide anti-tank support in combat operations but do not fit all the criteria of a tank. They may mount a high-velocity anti-tank gun but have an open turret, no turret at all or run on wheels instead of tracks. Vehicles which carry an anti-tank guided missile launcher are referred to as ATGM carriers.