Aside from the dimensions of the bag, the mil thickness is another critical component in selecting the right plastic bag for your needs.

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A Mil is a unit of measurement used to measure the thickness of film in thousands of an inch; 1 Mil = 1/1000 inch. While simple in principle, it"s very hard to visualize 1/1000 of an inch. Look around; is there anything that you can relate to 1/1000 of an inch? For example, paper is about 9 mils and a human hair is about 2/1000 of an inch or 2 Mils, but try visualizing two hairs stacked upon each other as a 4 Mil bag. This is where most people get lost; there are few things that we understand as being 1/1000 of an inch.

Mils are sometimes listed in decimal as thousands of an inch; a 2 mil bag may be listed as .002. To convert the decimal to actual mils, simply shift the decimal over by three, .004 to 4 mils.

Choosing the Right Mil Thickness

How thick of a mil needed is dependent on the application. If you"re product is heavy or has sharp corners, it would be a wiser choice to go with a heavier gauge than lighter. Vice versa, you would not want to place food items; fruits, vegetables, etc… in a 6 mil bag. Keep in mind that the clarity of a bag is affected by the thickness. A 4 mil bag would not be a clear as a 1 mil bag.

The best way to understand the thickness of a Mil is to use some perspective. Here are some common everyday bags and their associated Mil thicknesses:


A grocery store bag is 0.5 milA dry cleaning bag is 0.75 milA bread bag is 1.5 mils thickA freezer bags is generally 1.75 milsA retail shopping bag is usually 2 mils

Suggested Uses:

1 MIL - Economical short term storage.1.5 MIL - Lightweight protection from dirt and moisture.2 MIL - Protection for shipping and storage.3 MIL - Additional protection for hardware, nuts, bolts and industrial parts.4 MIL - Heavy duty protection when packaging nails, screws & heavy metal parts.6 MIL - Extra heavy duty protection against punctures and tears on bulky items or items with sharp corners.


About Measuring

1. Measure the width, depth and height of the box to be lined. The depth should be the shorter side.

2. To determine the Width (W) of the bag, add 1" to the width of the box.

3. To determine the Depth (D) of the bag, add 1" to the depth of the box.

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4. The Length (L) of the bag is determined by adding the depth to the height of the box plus 6" to allow coverage of the box contents.

Example: If the box size is 18"(wide) x 12"(deep) x 14"(high), the bag dimensions are as follows: Width (W) is 19" Depth (D) is 13" Length (L) is 32"