Daytona Twin Tec External 7-Pin Ignition Module Model 1006 for Harley Davidson Feature two advance curve families that are adjustable to accommodate stock and modified engines Selectable multi-spark mode for quick starting and smooth cruising Unit has four rotary switches for timing adjustments, single/ dual ignition mode and rpm limit (100 rpm steps) Coil outputs protected against short circuits Requires coils with a minimum of 3 ohms resistance and low resistance spiral-core-type plug wires