The Standard Motor Products FJ504 is a new, Multi-Port Fuel Injection (MFI) "spider" style injector assembly designed for 1996-2002 General Motors (GM) 5.0L and 5.7L V8 engines. It acts as a direct OE replacement, often used to convert or replace older CSFI systems, featuring high-temperature Viton O-rings and corrosion-resistant components for improved reliability and performance.