Welcome to the group.
I don't see it listed on the Standard Features, but being it's a 16' trailer, I'd have to say a the 2" flip jack is correct.
If in doubt, call Camping World. If they have a camper in inventory, ask someone to measure the jack tube. If your trailer is stored outdoors, call the attendant at the storage facility. Ask them to measure it.
Remember, these jacks are measured at the outer tube.
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