Amber colored glass helps protect your oils, tinctures, liquids, etc. from damaging light and UV rays. It’s advised to always keep bottles in a cool dark location, but when you do have them out to use it’s good to have a colored glass bottle. Many elements are also sensitive to plastic exposure and will degrade or change their chemical form if not in glass. Use for your own storage, attach labels to use for selling a product you make, or to give away samples of your mixtures as gifts.