There is a Dropper and/or Pipette for 5 ml, 1/2 oz, 1 oz, 2 oz, and 4 oz jars. Droppers screw onto the essential, fragrance and carrier oil jars. Pipettes can be kept (maybe by rubber band) with the oil it goes with so there is no cross contamination.
Dropper Combo fits in the bottle and allows for drops of oil to drop out when jar is turned over.