These bottles will hold between 20 and 40 drops.
You can use a plastic pipette, or glass dropper too fill the bottle. After you have added your oils to the bottle make sure to press firmly on the roller, this will help avoid leaking. Bottles containing oils or Liquid should be stored and transported upright to prevent leaking. Once all the oil is in and the cap is screwed on, you will want to label the vial so you know what it contains.