The ENYA head and front cover screws are metric. They are 3MM but they are not the same pitch as the OS screws(40FP). I know that they ARE the same as the older OS 35-S screws. I have used ENYA screws for the rear cover on the 30-S and 35-S engines. I could send you a set of screws AIRMAIL, but I need to check the postage with my PO.
Regards, Duane
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