# Tagging Materials When you tag a material with a name, you make that material available to be applied to any tagged mesh. For example by tagging a mesh with the name V\[**BALL**], and tagging two materials V\[**BLUE**] and V\[**RED**], you allow viewers to request the **BALL** with either the **RED** or **BLUE** material applied. You only need to tag materials you want to be available for applying to tagged meshes. Think of these tagged materials as a paint pallet you can then use on any meshes in the model. If you don't want to swap any materials, you don't need to tag them. Tags can only contain numbers, letters and the underscore ‘\_’ character. {% hint style="danger" %} Take care to tag the material name itself, **not** a mesh the material is applied to or the textures that make up the material channels. {% endhint %} --- # 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.variant3d.com/3d-content/tagging-materials.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.