After receiving approval, 4 million doses have been shipped out.

Last week, pharmaceutical company Johnson & Johnson received the word that their COVID-19 vaccine candidate was safe and effective enough to qualify for the FDA’s emergency distribution process. On Saturday, the FDA’s advisory committee met to decide whether to approve the vaccine for rollout, and eventually decided to give them the green light. With the approval in hand, Johnson & Johnson has wasted no time in delivering shots far and wide.

According to Johnson & Johnson CEO Alex Gorsky, they’ve already got a massive quantity of shots on deck, and they’re “on trucks as we’re talking.”

“We’re shipping 4 million literally as we speak,” Gorsky told NBC today. “Within the next 24 to 48 hours, Americans should start receiving shots in arms.”

Unlike Moderna and Pfizer’s vaccines, the Johnson & Johnson shot is single-dose, so you don’t have to get another one after a few weeks. It’s also the most stable temperature-wise, so it can be stored in an ordinary refrigerator instead of a carefully regulated freezer. The trade-off to these perks is that the shot is only 66% effective compared to the other two, though that’s actually not as bad as it sounds. In Johnson & Johnson’s clinical trials, the vaccine was 85% effective against severe illness, and 100% effective against fatal or hospitilization-requiring illness. It’s also important to note that this vaccine’s testing was conducted when cases were at their absolute peak and in regions with particularly nasty variants, so the data’s naturally gonna be a little different.

There’s now a third safe COVID-19 vaccine, so we asked Dr. Fauci to walk us through the newly-authorized Johnson & Johnson option: The way it works, it’s effectiveness, and whether he’d take it himself. (The answer is yes!) pic.twitter.com/Zb0eYQzNTU

— White House COVID-19 Response Team (@WHCOVIDResponse) February 28, 2021

Dr. Anthony Fauci has assured Americans that despite the statistics, the Johnson & Johnson vaccine will serve its purpose just fine. “If you go to a place and you have J&J, and that’s the one that’s available now, I would take it. I personally would do the same thing,” Fauci told NBC. He added, “It’s not the weaker vaccine. They are all three really good vaccines.”