My grandfather gave me this hat a while ago, but I was wondering if it was real.
if you have any questions about the hat, I will try and awnser as many of them as I can.
Edit: Sorry for the typo in the title
The blue band and trim with lack of wings insignia suggest that this is the cap of a non-flight officer in the Soviet Air Force, as seen here. Was your grandfather in the Soviet airforce in some sort of support role? My only hesitation is that the colours seem quite vibrant compared to the lighter blue often seen.
FWIW, the '58' isn't a unit marking, but just a size indicator.
