Your measurements seem right on, but there is one GIGANTIC caveat with cheap belts (two actually, but they go hand in hand).
The edges.
Many cheap belts have square cut edges which will cut into the fabric of your kilt like a chainsaw. This is made worse when at least one half of the belt is composite leather or plastic (VERY stiff).
Even worse than badly finished edges, there is a new product which I'm seeing more and more of in the commercial market. It is a sort of rubberized edge finish, which when applied makes it look like the edges have been slicked and finished in the traditional way.
Unfortunately this material doesn't have a terribly long lifespan and gets gummy and smears. My wife ruined a VERY expensive wool coat last year with a purse that had it's strap edges finished with this crap. (I won't even say that I warned her ahead of time for fear of being called petty)
At the end of the day, you get what you pay for. A $3.99 belt will most likely be worth (at best) $3.99. Placing your trust and the fate of a potentially VERY expensive kilt in it's hands is a leap of faith that I don't think should be taken lightly.
ith:














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