Features: A Nice Tool Kit For Repair Damaged Spark Plug Threads And Lengthen Spark Plugs Service Time. Made Of Hardened Carbon Steel, These Accessories Are Of Strong Strength And Long Durability. With Four Size Of Inserts For Different 14mm Thread Size Spark Plugs. Specifications: Material: Carbon Steel Color: As Picture Shown Thread Inserts: M14 * 1.25(10.9mm/0.429") M14 * 1.25(11mm/0.433") M14 * 1.25(12.9mm/0.508") M14 * 1.25 (17.9mm/0.705") Package Included: 1 * Re-Thread Tap 4 * Spark Plug Inserts Note: Due To The Light And Screen Difference, The Item's Color May Be Slightly Different From The Pictures. All Dimensions Are Measured By Hand, There May Be Small Deviations. .