The RNA Marker Low Easy is supplied in a ready-to-use mixture of loading dye (containing formamide, EDTA sodium salt, bromphenol blue) and RNAs. It is prepared for denaturing polyacrylamide gel electrophoresis but not agarose gel elctrophoresis. The RNA Marker Low Easy has seven single-stranded RNAs, 20, 50, 100, 200, 300, 400 and 500 bases. The 20-base and 50-base RNA are synthesized by chemically (not phosphorylated), others are synthesized by in vitro transcription. In 5 ul of the RNA Marker Low Easy, each RNA amount is approximately 100 ng. It is useful for estimating RNA amount approximately. The RNA Marker Low Easy can be visualized by UV light after ethidium bromide staining.