As used for oil or water gallerys. 8.0mm 8.75mm 9mm 10mm 12mm 12.5mm 14mm 14.5mm 15mm 16mm 17mm 18mm 19mm 20mm 22mm 24mm 25mm 26mm 27mm 28mm 29mm 30mm 32mm 33.5mm 34mm 35mm 36mm 36.5mm. I have been building and developing race engines for over 25 years 18 of those years where spent at mountune race engines.
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