It's from a 70's Italian mic (UMC 7103), a unidirectional condenser microphone. I need to substitute the original jack cable, with a XLR, but i don't know what is this connector (it screws on the mic)
Looks very much like a vintage Switchcraft 2501 connector. Note that those were typically used for vintage high-impedance unbalanced microphones. So even if you had a cable with that connector on one end and XLR on the other, it would likely NOT be suitable for a modern low-impedance balanced connection (as you get with typical XLR mic inputs).