Thread sizes below 1/4 confusing

These screws are common as common gets. For example, the common hardware holding your electrical wall switch plates and outlets trim plates on are commonly 6-32. Just google "machine screw thread size chart" or similar...................

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It is important to understand that these are "common" and "standard" sizes. Holley carbs, for example, "back in the day" never used standard thread screws. Guns.....AMERICAN guns commonly use specialized threads different than common machine screw sizes