Brown reagent bottles are suitable for chromatographic analysis and sample preservation of light unstable samples, as well as for the preservation of compound samples in the chemical, pharmaceutical, and research laboratories industries. Sample bottles are mostly made of borosilicate glass bottles, which are chemically inert glasses widely used in laboratories, especially in chromatographic analysis applications. Grade I glass is mainly composed of silicon and oxygen, with trace amounts of boron and sodium. It has low solubility and a linear expansion coefficient of 33.