These all-in-one precise measuring and dispensing caps are popularly referred to as Euro Vertical Dropper caps. This 18 mm white polypropylene (PP) plastic tamper evident closure has smooth top and ribbed sidewalls for a strong grip. when the cap is first applied to its bottle it forces a natural colored plastic orifice reducer and inverted vertical dropper tip into the opening of the bottle. When the cap is unscrewed, the tamper evident disc separates from the cap and the insert (that orifice and inverted vertical dropper tip) remains inside the bottle opening. This orifice insert drop-dispenses aromatherapy essential oils, herbal extracts, tinctures, and more. Tamper-evident band maintains product integrity, ensuring your product has not been compromised.