Hydration Internal

Hydration Internal
Hydration Reservoir?

I’ve just bought a new berghaus freeflow 35+8 rucksack. It says in the blurb that came with it it has an “internal bladder pocket for hydration reservoir” i was just wondering what actually is this?

internal bladder can hold water usually has a hose that can reach the wearers mouth so that by biting the hose you can get water that is held inside the pack. None of the websites on this pack seem to talk about this feature. this is what a bladder looks like.