# ExtractSrf
## 
ExtractSrf
The ExtractSrf command separates or duplicates polysurface, Extrusion, or SubD faces.
### Input
* Polysurface face
* Extrusion face
* SubD face
### **Steps**
Select the faces on a polysurface, an Extrusion, or a SubD.
> * The extracted faces will be removed from the group containing the source object.
> * To remove a surface from the selection, press Ctrl(CMD) while clicking.
### Command-line options
#### **Copy**
Specifies whether or not the selected faces are copied. A plus sign  appears at the cursor when Copy=Yes.
The RememberCopyOptions command determines whether the selected option is used as the default.
#### **OutputLayer**
* **Current**
Places the results on the current layer.
* **Input**
Places the results on the source object's layer.
#### **SubDAddCorners**
Creases the SubD corner vertices on the boundaries created by the extraction.
For more information, please refer to the [Rhino documentation](https://docs.mcneel.com/rhino/8/help/en-us/commands/extractsrf.htm#\(null\)).
---
# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://docs.rhinoartisan.com/commands/subd/creation/extractsrf.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
