Sourced SRC. Coordinate Reference System in which the current drawing is represented, which is selected by pressing the button ... and allowing its selection by area, code, favorites, etc.
Target SRC. Coordinate Reference System to which the drawing is intended to be transformed.
Element to convert
All drawing. If this option is selected, you will try to apply the projection change to all drawing entities.
Select Layers. This option allows you to select the layers to whose features the projection change will be applied.
Select Entities. If this possibility is chosen, after pressing the ACCEPT button, the designation of the entities to be projected will be requested.
Change layer of un-converted features. If this check box is selected, features in the drawing that could not be converted are changed to a layer whose name will be the original by preceding the value of the Prefixbox.