It's made by Robitussin. It's a cool mist. I add water to mine 2. Its a 1 gallon a day for small rooms.
Cool mist is ultrasonic. I feel that humidification techniques can cause dehydration. When growing Salvia was still new and not really studied, my leaves grew much larger healthier, signs of better hydration without occasional misting. Spraying the leaves with water cause them to curl and be more brittle, I think that, depending on the humidification technique, causes capillary action to actually remove more water.... my place is ridiculously dry though.
Ultraonic, however, should be a safe choice. The water vapor is so small it's absorbed instantly into the plants (~4 nm water droplets!)
Also is clean as distilled. Considered a dry fog/mist. If used in aeroponics, only needs 25% usual nute dose, 50% max to prevent burning. A lot higher efficiency, with smaller rez and easier setup.