The accepted way to measure the thickness of something such as Plastic Bags is to use Microns or Mils.  However not both together.   The reason it has to be one or the other is that these are units of measure that are using two completely different systems. 

Mil is a unit of measurement in the English system.  1 Mil is 1/1,000 of an inch or .001

Micron is a unit of measurement in the Metric system.  1 Micron is equal to 1/1,000 of a millimeter.

If you need to convert one to the other, 25.4 Microns equals 1 Mil.

The formula to covert Mils to Microns: (Number of Microns) x 25.4 = Mils   So if it’s .75 Mils it’s .75 x 25.4 or 19 Microns.

The formula to covert Microns to Mils: (Number of Microns)/25.4 = Microns   So if it’s 12 Microns it’s 12/25.4 or .47 Mils.

Our line of High Density T-Shirt Bags are all measured in microns.

Hopefully you do not have to convert, but sometimes it is necessary to get the correct comparison if two companies are using different systems.  Fetpak uses both systems because we use the standard unit of measure on a particular  products.  For example we use mils on our Packaging Tapes and microns on our High Density T-Shirt Bags because those measurements are industry measuring standards and are generally accepted by purchasers.

You may want to keep the conversion formulas for your records, this way you can always tell which is the thicker product no matter which system is being used.