1.    Does it come with auto shut off feature?

Yes, when the water run out, it will switch off automatically

2.    What is the capacity?

About 300ml，it produces up to 30ml of moisture per hour and can run for up to 10 hours of continuous output

3.    How many drops of oils should be used?

It depends but the device demands not more than 3-5 drops of oils or else it will corrode

4.    Can I adjust the output of the mist?

Yes, it has 3 options, low, medium and high

5.    Can you use it without the oils - just as a humidifier when desired?

Yes, you can add water to it only, it will work as humidifier

6.    What is the reservoir/casing made of?

The reservoir and casing are made of BPA free PP, which is the same material used to baby bottles.