I have a nice tiny ultrasonic humidifier which has several issues: - it is designed to accept PET bottles only - it is almost impossible to clean the vapor head properly - if turned on it will illuminate a disgusting strong blue light thru the original transparent acrylic vapor head I have modeled the original vapor head (slightly modified to make it printable w/o supports) so you can print a new, non-transparent one. As I don't have any PET bottles here at home - but have several Sodastream tanks - I have also created a Sodastream to PET bottle converter. Link to the vapor head design: https://a360.co/2CUoCaG Link to the Sodastream to PET converter design: https://a360.co/2QBYnK8