Constructed from plastic, glass, borosilicate glass or soda-lime glass, reagent bottles feature stoppers or caps, which protect the contents from spilling or outside environmental contamination. Reagent bottles are excellent for storing powders and liquids. Reagent bottles in tinted amber or red protect light-sensitive contents from UV light, visible light and infrared radiation. Reagent bottles are available with narrow mouths for better control while pouring, or wide mouths for easy filling or content retrieval. Caps and stoppers for reagent bottles should be selected carefully, as their material or lining may interact negatively with the contents of the bottle.