Mallory 605 Unilite Ignition Module (Thermalclad) Module will fire below 75 RPM This module is very accurate as a triggering devise Module requires a 1.4 ohms ballast resistor with it Module uses a shutter wheel to trigger This module simply bolts in an doesn't require any adjustments Highly accurate, reliable and simple ignition trigger and amplifiers Highly durable Combined with modern surface mount Thermal-Clad? construction, these ignition modules can drive both OEM and high performance ignition coils