I have the Number 1 model fixed into my Bobelock violin case. It only needs refilling about once a week or so. Here's another gizmo - Herco guitar humidifier. It also works well - I use it in my other case.

With the very cold weather we've had the humidity gets quite low and the fiddle pegs start slipping - nothing like a bad peg day! But one of these things in the case cures the problem.

Cheers, S. in Seattle