01
First — ribbon, or no ribbon?
Exactly the decision on the ZD220, and it matters more than anything else here. Direct thermal for labels read within weeks; thermal transfer for anything that has to still be readable next year. Get this wrong and the printer is fine but the labels are unreadable.
02
Second — how it connects, now and later
USB belongs to one computer. Ethernet belongs to the network, so a system can print to it rather than a person. Wireless suits a bench that moves, or a building where running a cable is the expensive part — and on this page wireless comes on the thermal transfer versions. If you want direct thermal and wireless together, ask: Zebra is mid-transition on those part numbers and we would rather quote you one that is still going to be here.
03
The slot is the part worth understanding
The wireless versions carry a modular connectivity slot. That is what stops today's decision being permanent — the way the printer connects can be changed later without changing the printer, which is worth having when nobody can say what the network will look like in three years.
04
Two wireless versions, and the newer one is cheaper
The two wireless part numbers differ only in which radio is inside. PX02 is Wi-Fi 6 — 802.11ax with Bluetooth 5.3 in the table below. PW02 is Wi-Fi 5 — 802.11ac with Bluetooth 4. Same printer otherwise. The newer radio is the cheaper of the two, $911 against $925, so unless you have a reason to match older access points the answer is the Wi-Fi 6 version. That is the sort of thing a part number will not tell you and we will.
If one PC prints the labels and always will, buy the ZD220. It does the same four inch label for a hundred dollars less and we would rather sell you that than something you are not using. This printer earns the difference when a second person needs to print, when a system does it instead of a person, or when the printer has to keep working through a change nobody has planned yet.