All orders are packed frozen into insulated shipping boxes with dry ice.
Every order starts with 10-15 pounds of dry ice per package.
Keep in mind that dry ice is a solid form of CO2.
Dry ice is -109.3°F or -78.5°C and dissipates at approx 5-10 pounds per day.
Enough dry ice is packed in each order to assure that the rodents arrive frozen.
Even though most or even all the dry ice will be dissipated when you open the box, the product will still be frozen.
If there is still dry ice in the package when it arrives be very careful handling it as it will burn and place outside as soon as possible because it is an inhalation hazard.