Only pumps out about 2.2L
My engine holds 2.7L of oil - so it could have been the perfect size.
Unfortunately, there is no information (from the manufacturer) about the maximum suction quantity.
A nice employee at SVB recommended that I try it with water first - good tip, because only about 2.2L is sucked out.
Then the float is pushed and seals, which is also a good thing in principle.
So for the next one, here is the net filling quantity 2.2L )