CYLINDER HEAD TEMPERATURE GAUGE/Electronic, 2 1/4, 100-600 degree Fahrenheit, black and white dial with wire leads, requires Type J thermocouple probe 12-460-600F2 1/4" ELEC. PRESS AIR-CORE 270° SWEEP W/ PIG-TAIL WIRE LEAD 2 1/4" CHT 100-600° F B&W (requires Type J Thermocouple probe) 12-460-600F2 ..