[press9761]

(I'm not sure where I should post this message, forgive me if it's in the wrong location)

I have to make and bottle 1L of 20% Ammonium bifluoride into 10 100ml bottles.
I'm a bit concerned about safety and want to set up a system so that this can be done without the risk of spilling.
Also, I know that Ammonium bifluoride is a glass-etchant, I think a 20% solution is ~4 molar.
I don't know if this would be considered a strong or weak concentration.   

Anyway, I have been making small batches of pH buffers by mixing XYZ powder and acid/base in a flat bottom florence flask (on a stirrer plate).
Then I simply pour out the continence into a graduated cylinder (using a funnel).
This spills a drop or two here and there.

I am not comfortable with this method for the Ammonium bifluoride.

I am thinking there must be a way to mix the Ammonium bifluoride powder and the pour it into a bottle using some type of
valve system.
However, all of this is kind new to me and I don't know the correct terminology to use nor do I fully understand how to ask the question.

So, I hope this helps you understand what I am trying to do.
Does anyone know what the equipment that I am looking for is called?
Can I use glass?

Thanks so much!!