This policy setting will allow the showing of both US Units and Metric Units when you create a new blank drawing or stencil.
If you enable this policy setting, both US Units and Metric Units are shown as a choice before you create a new blank drawing or stencil. These drawings open with the appropriate rulers and page setup and use the appropriate units for the drawing tools. This does not install the templates and stencils in both unit types. This policy setting is always enabled whenever the Developer Tab is turned on.
If you disable or do not configure this policy setting, you are not shown a choice between units when creating a blank drawing or stencil if templates and stencils of only one type of unit are installed.