Another, very similar pair of military mittens, this time from Germany, has it’s own fibre pile insulation built in.
These are good, and slightly better for dexterity but have the disadvantage is that the lining cannot be removed for drying.
A good solution and somewhat easier to find on the market too.
If I just need a simple pair of mittens, these are great.
Typically, the British Army cold weather Mitten system used to be very poor, I believe this situation has improved since these were issued.