MIL is a unit of measurement commonly used in packaging to indicate the thickness of a material. One mil is equivalent to one-thousandth of an inch (0.001 inches or 0.0254 millimeters). In the packaging industry, MIL is often used to describe the thickness of plastic films, such as those used for flexible packaging, shrink wraps, or poly bags.
 
For example, a 3-mil plastic bag would have a thickness of 0.003 inches. The higher the MIL value, the thicker and generally stronger the material is, which can offer greater durability and protection for the contents during shipping or storage.
 
This measurement is critical when choosing materials for specific packaging needs, as it directly influences the protection, flexibility, and overall performance of the packaging material. Speaking with a packaging specialist can help you understand the right thickness of material needed for your packaging projects.