These glass droppers fit our 1 oz amber boston round bottles (20-400 thread). These droppers are nice because they can rest inside the vials as you work. Also, they are perfect for hosting your own perfume making parties, where scads of disposable pipettes would just clutter the workspace and cause confusion. Not to mention the benefit to the environment, as you are not disposing of all that plastic every time you work! Downside: since you’re keeping these for reuse, you do have to clean them. Or have your minions take care of it for you.
Although these droppers WILL screw onto the 1 oz amber boston round, they are NOT meant to be used as a lid for permanent storage. Rubber and essential oils do not play well together. Trust us – we learned this the hard way when we first started, thinking, “well, I see essential oils and fragrance oils sold in stores with glass droppers in the bottle! Let’s try it.” You know what happened? Our rubber stoppers expanded, and expanded, and then started turning into sludge down at the base. And they MELTED ONTO OUR VIALS. The oils were ruined. Obviously those oils sold in stores are highly diluted. Ours aren't. Do not try this at home. Rubber droppers are great for show, for parties, and for the environment. But they are not great for storage.
This also sounds like an excellent time to remind you that our fragrance oils are HIGHLY CONCENTRATED, and not diluted with alcohol or oil. Do not use undiluted on the skin.