WB-MASTER Protein Standard is designed for convenient protein identification in western blot. This standard consists of seven recombinant proteins with molecular weight of 20 kDa, 30 kDa, 40 kDa, 50 kDa, 60 kDa, 80 kDa and 120 kDa. Each of the proteins contains an IgG binding site that is able to bind to primary or secondary antibodies derived from a wide range of host species. The standard thus enables direct visualization of both the protein marker and users' samples on the same western blot membrane without any additional reagents.