OK, that means I need it. :-) Can you also say where and how it needs to be placed or inserted? Looking at it, it looks like it should be inserted into the 'cap' of the RO unit. If so, should the tiny black tube go 'up' the hole in the cap? Or the other way, so that the black tube sticks out into the cavity of the cap?
Sorry for the ignoramous questions here. I just want to get it set up correctly (of course!) ..Karl