Heavy Duty Ceramic Resistor for use with Ignition Coils. These resistors reduce point pitting and burning. They will extend point life. Used to supplement the ignition coil's primary resistance. Ballast resistors have been used for many decades to reduce current to the points or electronic ignition module, extending their lives. Also helps to protect electronic ignition conversion kits from overheating due to excess electrical current. Usually mounted on the firewall or on the ignition coil. Wired between the coil's positive terminal and the condenser or electronic ignition module.