TIGHTS UPAdjustable Stretch Elastic Belt Women - No Show Flat Buckle Ladies Belts - Non- Slip Backing | Belts for Women

I have crohn's and fluctuate between a size 16-20 will this be long enough please?

I cant find the plus size to order

How long does the belt measure, in cm? I know it can stretches up to whatever size; but how long is the belt as it comes? thanks.

Perhaps it's just me, but I can't work out a way to open this belt - yes, the buckle unclasps, but not the belt itself apparently. Can someone help?