Demand for sub-zero freezers has erupted over the last month following encouraging COVID-19 vaccine developments from Pfizer and the German firm BioNTech.

The Pfizer-BioNTech vaccine has to be stored at -70 degrees Celsius – standard commercial freezers don’t get that cold – forcing many hospital systems across the country to panic buy these special freezers from refrigerator-maker So-Low Environmental Equipment. 

Dean Hensler, vice president of So-Low, told CNBC’s Squawk on the Street that “right now we are out of everything.” 

Hensler said the anticipation of coronavirus vaccine distribution had unleashed a massive buying wave of ultra-cold freezers by hospital systems that plan on storing then distributing the vaccine. 

Last week, Pfizer-BioNTech filed for emergency use authorization with the FDA for approval – a meeting had been scheduled for Dec. 8, 9, and 10 – Pfizer CEO Albert Bourla said the first doses of the vaccine could be shipped out within hours of the EUA approval.

Reuters quoted President Trump on Thursday evening, saying the vaccine could begin delivery as soon as next week. 

The largest hurdle for a nationwide vaccine rollout is the expanding need for cold storage. 

“We had heard that the Pfizer was going to have to be stored at minus 70. We took it upon ourselves to say, ‘Hey, listen, we’ve got to do something about this,'” Hensler said. 

“Our phones started ringing off the hook the day it … got out to the public. That inventory we had built was gone like in three weeks, so now we’re building everything per order,” he said. “We’re running about six to eight weeks on delivery right now. It’s been crazy. It’s been crazy.”

“We’re going to work Friday after Thanksgiving,” Hensler said. The way the company sees it, he said, “The quicker we can get freezers out, the more people can get vaccinated, and we can get back to the old normal, rather than this new normal.”

Earlier this week, UPS announced it would produce thousands of pounds of dry ice per day and provide cold storage facilities and transportation for COVID-19 vaccines.