Ready To Run Distributors have a built-in ignition module, so an Ignition Control such as a MSD 6A box is not required. They’re simple to drop in and connect with three wires (power, coil negative and ground) making them favorites for street rods and muscle cars.
MSD Street Fire - Distributor - GM EFI V8 - 1988-95 - External Coil - Black
MSD - Ready to Run Distributor - Chevrolet 409 / 509 - Aluminum Block RTR - Red