We have the ATC221FR cart. This is the ATC221 cart with the AFR8 wheels. This cart works great for moving the weight of this tank around in the shop. The modification was to cut a round hole in the top and middle shelves, large enough to hold the tank. Cutting the holes wasn’t bad; one drilled pilot on the circle we drew after looking at the bottom support ribs, then using a saber saw we cut the circle. To smooth off the edges a wire buffing brush for the drill worked out great.
You can take the top and middle shelf off to change out the tank. You just move the tank onto the lower shelf then put the middle and top shelf back on.
ATC221FR