Engineered to be the only true performance Ford 4-tower style EDIS coil. Advanced bobbin technology, highly specialized silicone magnetic steel core, optimized winding, resistance, and turns ratio result in higher energy and voltage outputs, and longer arc duration. Direct OEM replacement. Must use factory firing order. Compatible with Ford EDIS computer controlled ignition system as well as Crane or MSD capacitive discharged (CD) DIS ignition systems. Special high temperature epoxy resists shock and vibration, while increasing thermal conductivity. Secondary towers molded in high dielectric strength ACCEL Yellow. Packaged as single unit; 4 cyls require 1 coil pack, ""twin plug"" 4 cyls require 2 coil packs and 8 cyls require 2 coil packs. No tsuitable for some late 1999 applications