CADWorxP&ID tab: Size_Spec > Size Set 
CADWorxP&ID tab: Setup > Setup 
> Size
Size / Spec toolbar: Size Set
Setting toolbar: Size
P&ID menu: Accessory > Size > Set
Command line: SIZEDLG, MAIN, or RED
Specifies main and reduction sizes. This command displays the Sizes dialog box.
Main
Sets the selected row as the main size.
Reduction
Sets the selected row as the reduction size. This option is not available until Main is set.
Clear
Removes the selected main and reduction sizes and closes the dialog box.
OK
Accepts the selected main and reduction sizes and closes the dialog box.
The list of available sizes is controlled by [Product Folder]\P&ID\System\SetSize.Tbl (English/inches), SetSizeA.tbl (Metric/inches), and SetSizeM.tbl
(Metric/mm).