33R Carbon fiber front bumper lip splitters for the BMW G80 M3, G82/G83 M4 are popular aftermarket upgrades, typically 3-piece kits (center lip + corner splitters) made from lightweight, durable dry or pre-preg carbon fiber, designed to enhance aerodynamics and give a more aggressive, lower look by either adding onto or replacing the OEM black splitters, often using existing mounting points for relatively straightforward, sometimes DIY, installation.