Freeze cells in tubes from 1 to 5 mL using the Thermo Scientific™ Mr. Frosty™ Freezing Container. The simple-to-use system is designed to achieve a rate of cooling very close to -1°C/minute, the optimal rate for cell preservation. It holds 12 to 18 tubes, and a screw top lid secures samples inside in the event of accidental container tipping.