Broad Multi Color Pre-Stained Protein Standard is a special-designed protein standard. The standard is a mixture of ten highly purified prestained proteins ranging from 5 kDa to 270 kDa, covalently coupled with four different chromophores. The 30 kDa band is red, 50 kDa band is green, 270 kDa band is orange, and other bands are blue. Broad Multi Color Pre-Stained Protein Standard is designed for observing protein separation during SDS-PAGE, verifying western transfer efficiency on membranes, and approximating the size of proteins.