CoolRack Microfuge racks are thermo-conductive tube holders to keep microfuge tubes at temperature during experiments. They maintain temperature through direct contact with ice, dry ice, water, or liquid nitrogen and prevent tubes from tipping, floating, or contamination from the temperature source. Sizes available - M series: 15 tube, 30 tube, 90 tube, 96 tube in cylindrical hole configuration MPF series: 15 tube and 30 tube in profiled fit for conical 1ml, 1.8ml, 2.0ml tubes for rapid temperature shift experiments and snap freezing. The MPF (profiled fit) will snap freeze samples without alcohol and faster than immersion in alcohol/dry ice slurries. This allows snap freezing without risk of losing tube labels in alcohol solvent.