I have noticed, several times over the years, that OxYoke pre-cut patches all measure .003" to .005" thinner than what the package indicates.
The OxYoke .018" patches for me, measured .014"/.015" in my calipers, compressed.
Best to get some 8, 10 & 12 ounce denim and have at it. The 8 ounce I measure at .018", the 10 at .022" and 12 ounce, at .030"- compresses hard in my calipers.
You can subtract a few to up to 4 thousandth's for a hard compressed mic measure on this stuff.
I edited this post to change the word "smaller" to "thinner".
Thinner than stated is the correct wording.