These Glass Droppers come with their own labeled glass vial, which allows them to be safely stored away from the Essential Oil Bottle. This protects the rubber bulb from deteriorating from prolonged exposure to the Essential Oil; as most Essential Oils over time will deteriorate any rubber material.
Please Note: The Essential Oils sold in The K9 Nose Kits do have a built-in orifice reducer that allows the essential oil to be dispensed one drop at a time. The oils that do not have an orifice reducer are Myrrh & Vetiver due to the viscosity of the oil itself. There is also the option to purchase many of the Essential Oils without any oil dispenser.