The Ambion® Single Tube Magnetic Rack holds one 1.5 mL microcentrifuge tube. When using this rack, as with any magnetic stand, centrifugation is replaced by attraction between the captured beads in solution and the magnet on the rack, causing the beads to collect on the side of the microcentrifuge tube. As a result, captured substances such as mRNA can be separated quickly and efficiently from other components in the solution.