This is Swedish brand Tac-Up Gear’s Thermal Cap (Nordic Conditions Water Resistant) in M90 camouflage.
It features a fleece liner and a seam aped membrane for weather resistance. The outer shell is ripstop fabric. The bill can be secured in the up
position via Velcro and there is a bungee adjustment at the rear to keep the cap from blowing off in high winds.
Available in XSmall, Small and XLarge.
tacupgear.com/all-products/thermal-cap-m90
That reminds me of something I’ve wondered about for awhile. Do the US Army & Marines issue some kind of ski mask for extreme-cold-weather wear? I’m aware of the fleece cap, and it seems like I’ve seen a version with a longer back to cover the back of the neck. But I’ve never seen a pic of something covering the face.