Do I need a special freezer for the Varicella Cool Cube™ panels? L Do I need a special freezer for the Varicella Cool Cube™ panels? Your freezer must be below at least -15°C. -25°C or below is recommended to get the panels solid (for maximum hold time). The colder the storage environment, the less time is needed to condition the panels for use. Post navigationNext post: What is the difference between Excursion-Trac™ and Memory-Loc™? Leave a Reply Cancel replyYou must be logged in to post a comment.