Re-Freeze-R-Brix is a block of rigid open cell foam refrigerant impregnated with a specially formulated non-toxic aqueous solution and hermetically sealed in a heavy-duty plastic pouch. Use to prevent thawing of frozen samples and prevent warming of heat labile samples. Re-Freeze-R-Brix can even be warmed with hot water, to slowly release heat to safeguard against freezing. Several different sizes are available. To determine the amount of Re-Freeze-R-Brix needed for a specific application we recommend that shipping and storage tests be done.