GROTECHNICA IMPEX PRIVATE LIMITED offers the best 30 ml Clear Dropper Bottle 18 mm Special Neck which has an 18 mm Special Neck. They are inert and non-reactive which adds on to their many qualities. These glass bottles are pharmaceutical and nutraceutical industry favourites as they are USP Type III tested, 100% non-toxic and 100% lead free. These dropper bottles increase shelf life of the products.