Probably the most common improvement for off-road use is the grille or bull guard, which can be added with or without an improved bumper. These typically metal frameworks extend to protect the grille, and potentially the headlights as well. One common type used on off-road pickups and SUVs is the "prerunner" style, with an angular, protruding front designed to sweep vegetation away from the vehicle centerline, and to deflect the vehicle from less movable obstacles. The grille protection system can be assembled piecemeal, or a one-piece winch-mount bumper with a prerunner bar and grille guard can be fitted. Bumpers designed for off-road use typically have added eyes or D-rings to assist in vehicle recovery.