Black Chevy Tall Deck Dual Sync Distributor Pro-Billet Dual Sync EFI Distributors Designed To Work With Holley Efi, And Other Sequential EFI Systems That Support Hall Effect Crank And Cams Sensor Inputs MSD IgnitionWhile these distributors are designed primarily for use with sequential fuel injection systems that support Hall Effect crank and cam sensor inputs, they can also trigger TBI fuel injection systems. The precision machined shutter wheel design ensures accurate timing, even at high engine speeds. If you've converted to a coil per cylinder ignition system, we offer a great looking blank distributor cap to save space and eliminate the unused cap and