Size .394". Flex-Hone allows you to precision fit valve stems to proper guide tolerances. It is self aligning to the guide bore and self compensating for hone wear.
This tool simplifies magneto timing on TCM (Continental) series O-300 A & B engines. No protractor on the spinner required, or other complicated tooling. Simply place it over the prop nuts and sight down the casing split to set the timing.
A reliable liquid gasket sealant, dressing and coating compound that brushes on very thinly and resists temperatures of -65º to 400ºF (-54ºC to 204ºC). It will not interact with other chemicals, and dries to full strength in under 12 hours.