Black steel replacement lower guard. Fab Fours is an industry-leading Truck & Jeep Bumper and Accessories manufacturer dedicated to pushing the boundaries of innovation in every product that we develop. Fab Fours is the market leader in premium bumpers for both Truck and Jeep, and we continue to expand our product offering. By combining the best 3D design capabilities, strong and consistent product DNA, and flexible on-site prototyping capabilities, Fab Fours has the confidence to continue to lead the industry.