These canisters come threaded or unthreaded, but the video at this site elides this distinction. You need to buy the cannisters from someone else. Be sure to get the threaded ones to go with this inflator.
Maybe they now address this; they hadn’t when I made the mistake of buying unthreaded cannisters.
A year in and I have yet to use this on the trail, which is the insurance you buy when you get a nice product like this. I'm still confident in it when the day comes