Our s-chassis bash bars are designed to fit under/behind the factory bumper (which includes most, if not all, aftermarket bumpers). On certain bars, they are designed to support the bumper as well. This includes s13 front bash bars (designed to support silvia bumpers), s13 hatch rear bash bars, s14 (zenki and kouki) front bash bars.
Our aftermarket bash bars cut the weight of the factory bar by more than half! They are lightweight, yet strong and sturdy. Weighing just under 14 pounds (with jack point) versus a factory bar at almost 33 pounds!