From the PSA website:
Barrel: 10.5" 4150V Chrome Moly vanadium steel, nitride treated for durability and chambered in 5.56 NATO with a 1 in 7" twist.
https://palmettostatearmory.com/psa-ar15-10-5-5-56-nato-10-5-1-7-carbine-nitride-barre.html
.750 gas block diameter
M4 barrel extension
Muzzle...