About Shrinkwrap Features
A Shrinkwrap feature is a collection of surfaces and datums that represents the exterior shape of a model. You can use a part, a skeleton, or a top-level assembly as the source model for a Shrinkwrap feature. By default, the system automatically analyzes all components in the assembly and determines which ones will be included in the Shrinkwrap. However, you can select specific components for shrinkwrap consideration while ignoring others.
The Shrinkwrap feature is created in the object that is currently being modified. All created geometry appears in the modified object. The system captures source geometry by using surfaces, datum geometry, and such customized attributes as hole filling, and quilt inclusion, according to your specifications. You can also create a shrinkwrap feature as an assembly internal volume.
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Shrinkwrap features do not copy geometry from the level on which they are created.
Shrinkwrap features conserve system resources because they include only the exterior shape of a model. Shrinkwraps of subassemblies can be useful for the manipulation of large assemblies since they reduce the memory space required for working on the source parent assembly.