Plug Tap M14 x 1.25 (HSS 4241). Step Tap M14 x 1.25: M15.8 x 1.25 (HSS4241). Threaded inserts: M14 x 1.25 (10 x 15mm, 10 x 9.4mm length). The Plug Tap is used to clean the original thread, followed by the Stepped Tap which locates using the original thread as a guide and cuts a M15.8 x 1.25 thread.
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