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Faces can be extruded from/into the body of an object to create extensions or depressions. This moves the original face and adds new faces along the axis of movement. You can extrude multiple faces simultaneously. You cannot extrude if the Edit tool is in Selector Mode.
To extrude select the face/s you want to extrude using the Edit tool. Selecting SMesh Faces
Hold down the Shift key anf and click on the face you want to select.
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