Reagent bottles, also known as
media bottles or
graduated bottles, are containers made of
glass,
plastic,
borosilicate or related substances, and topped by special
caps or
stoppers and are intended to contain
chemicals in
liquid or powder form for
laboratories and stored in
cabinets or on shelves. Some reagent bottles are tinted amber (actinic), brown or red to protect light-sensitive chemical compounds from visible light, ultraviolet and infrared radiation which may alter them. The bottles are called "graduated" when they have marks on the sides indicating the approximate (rarely exact) amount of liquid at a given level within the container. A reagent bottle is a type of
laboratory glassware. The term "
reagent" refers to a substance that is part of a
chemical reaction (or an
ingredient of which), and "media" is the plural form of "
medium" which refers to the liquid or gas which a reaction happens within, or is a processing chemical tool such as (for example) a
flux.