RODI Water Filtration: Liquid in PSI Guage?

[slingfox]

I am new to the hobby and am in process of setting up my first tank (it will be a Red Reefer 525 G2---go big or go home right?)

I just purchased a 5 stage RODI system from BRS. Out of the box it looks like the PSI guage has some sort of oily liquid inside. Is this normal? See picture below:

 

[Gtinnel]

I’m guessing it’s a glycerin filled gauge and perfectly normal.

 

[adadwa]

The liquid in the gage is glycerine. It helps to dampen vibration and stabilize the needle.

 

[slingfox]

Thanks guys, I appreciate the quick feedback!