They write it:
It is Cordura Nylon.
9,05 lbs (=4082g)
That's a very heavy, very tough and long lasting very large rucksack.
It depends on the own body size and strength if that's a good choice.
In my opinion it's to heavy, but men who are 2 meters tall and farmers, gardeners or who work in another job like that could probably carry it, even if it's full.
I think it isn't good for free time hiking, but probably good for winter camping, if long distance hiking isn't the idea.
If it's full with a winter camping equipment, food and water, the total weight surely reaches between 20 and 30 kg.
I always try to stay under 16 kg all together.
This rucksack here is made from the same fabric but weights only 1400 g, volume 65 litres, with the option to attach a winter sleeping bag on top of it.
It's original German Army, the price is for a used rucksack in usually good conditions.
https://m.asmc.de/BW-Kampfrucksack-flecktarn-gebraucht
This very thin folding insulation mat has to be used in it as the back padding.
(Original German Army, used 425g)
https://m.asmc.de/BW-Isomatte-faltbar-gebraucht
I find that system comfortable until max 16 kg, 18 kg is the absolut maximum I would carry in and on top of it over shorter distances.
It has no hip belt. It isn't made to carry such high loads in it.
The really comfortable weight is between 7 and 13 kg. And I have no problem to pack my winter equipment like that, including the Snugpak Special Forces complete sleeping bag system attached on top of the flap. It is recommended until -20 *C I think.
But yes, if you want to put a spare winter suit in this rucksack you will get problems.
It was designed to defend Germany with normal soldiers, civilians in uniform, not to conquer Alaska with well trained special forces.