Pitch: M6 - 1mm Pitch ; M8 - 1.25mm Pitch ; M10 - 1.5mm Pitch, M12 - 1.75mm Pitch. M8 x 49mm for 22mm external pipe M12 x 78mm for 42mm external pipe. M8 x 54mm for 27mm external pipe M12 x 84mm for 48mm external pipe.
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