The bolt in your parts bin is American 7/16 UNF - a common size.
0.75mm pitch (approx 33.8tpi) is a fine thread more suited to small holes in soft alloy. A manufactured bolt in 33.8 tpi simply does not exist.
BA-3 which is approx 34.8 tpi and 4.10mm in diameter is the nearest imperial equivalent to 0.75mm pitch.
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