A-254 - Temperature Sensor, NTC Type, Spark Plug (14mm) Max: 285C/545F. 40cm 

Application: Spark Plug / Cylinder Head (CHT) 
Maximum Temperature: 285°C / 545°F 
Spark plug: 14mm 
Length: 40cm / 15.7 inch 

Important note: This sensor must be used with an extension

Works with ASTRO, PROv2, and PRO+
NOTE: Uses A-351 Extension cable