The first letter(s) of a Denso, NGK and Bosch plug code is the thread size identification. Denso: X, XU.
Sealey Spark Plug Thread Chaser 14 & 18mm Automotive Garage Vehicle Service
Sealey Spark Plug Thread Chaser Reverse Action 14mm Repair Engine Damage
Sealey Spark Plug Socket 16mm 3/8" Square Drive Thin Wall Spark Plug Socket
14mm Back Tap Spark Plug Thread Repair Tool M14x1.25 Thread Chase Tap
1Set Stainless Steel Spark Plug Thread Repair Tool with M10x1.0 Thread Inserts
