The ProSieve™ QuadColor™ Protein Marker is a mixture of 12 recombinant, highly purified proteins with molecular weights of 4, 6, 10, 15, 25, 40, 55, 70, 100, 140, 170, 250, and 300 kDa. the proteins are individually prestained using four different dyes, producing a brightly colored ladder with an easy-to-remember pattern. The ProSieve™ QuadColor™ Protein Marker is ready-to-use: no heating, further dilution or addition of a reducing agent is required before use