Click the 
	 Features 
	 
 step in the 
	 Steps panel. 
  
 
	 
The top and bottom page is displayed. The top and bottom surfaces are extracted from the surfaces, but you can select different points to change the top and bottom heights of the feature.
The 
		Top & Bottom page enables you to set the top and bottom Z levels for a milling feature. You can enter these dimensions or select them using the 
		Pick location 
		
 button. When you pick the locations, the dialog warps out of the way until you complete your selection.