Features INSERTS AND TAP: Including 10pcs M14 x 1.25 thread inserts and a M16 x 1.25 thread tap, is professional spark plug thread repair tool kit. STAINLESS STEEL INSERT: These thread inserts are made of stainless steel, with galvanized technology, wear and corrosion resistant. HIGH SPEED STEEL TAP: The thread tap is made of high speed steel material, which has high hardness and heat resistance. STANDARD THREAD: These inserts and tap have standard thread, the general size is suitable for repairing 14mmx1.25mm spark plug. APPLICABLE MACHINE: Tapping is efficient and labor saving, very suitable for gasoline engines, generators, engines, etc. Specification: Item Type: Spark Plug Thread Repair Tools Thread Insert Size: M14 x 1.25 (thread diameter x pitch) Thread Insert Length: Approx. 17.5mm / 0.7in Thread Insert Material: Stainless Steel Thread Insert Process: Galvanized Tap Size: M16 x 1.25 (thread diameter x pitch) Tap Shank Diameter: Approx. 10mm / 0.4in Tap Full Length: Approx. 110.7mm / 4.4in Tap Blade Length: Approx. 33mm / 1.3in Tap Material: High Speed Steel Package List:1 x M16x1.25 Thread Tap 10 x M14x1.25 Thread Inserts Package List 1 x M16x1.25 Thread Tap 10 x M14x1.25 Thread Inserts