In the ConfigurationManager, right-click Envelope 
, and select Show/Hide Using Envelope.
Lets you specify selection criteria to hide or show assembly components, based on their positions relative to an envelope component.
To apply criteria to an envelope:
In the ConfigurationManager, right-click Envelope , and select Show/Hide Using Envelope.
The Apply Envelope dialog box appears.
Choose one or more Criteria for selecting the components:
Inside envelope. Components that are completely inside the envelope are selected.
Outside envelope. Components that are completely outside the envelope are selected. This includes components that are outside the envelope, but have a face that is coincident with the outside of the envelope.
Crossing envelope. Components that cross the boundary of the envelope are selected. This includes components that are inside the envelope, but have a face that is coincident with the outside of the envelope.
Choose Show part components or Hide part components.
Specify what to do with any component that does not meet the selection criteria:
With Show part components, you can either Hide it (regardless of current display state), or Leave its show/hide state as it is.
With Hide part components, you can either Show it (regardless of current display state), or Leave its show/hide state as it is.
Click OK.
The display is updated to hide or show components according to your selections.