# What materials are the Custom Alpha templates suitable for? What are the special parameters? The only special parameter of this template is the "Opacity Map" parameter. But there is a slight difference with the "Opacity Map" in the Cloth material template. There is no semi-transparent effect here, the material is either **completely preserved or completely hollow**. Therefore, here it is recommended to use only black and white map to control the hollow effect. * White is the material that is preserved, and black corresponds to the hollow position. ![](/files/-Mker6UJPFSjcsgLKwHY) {% hint style="info" %} In the range of 0\~255, Opacity Map gray value greater than 157, the corresponding material will be retained, and gray value less than 156, the corresponding material will be hollowed out. {% 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.d5render.com/user-guide/material/custom-alpha.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.