This fits the new FRC radio and is designed to hold a 60 or 80-milliamp fan it blows air through the built-in ducts and pumps it out the sides.
fan link: https://americancableassemblies.com/sr-component-70-6012-60mm-12vdc-brushless-cooling-fan/?sku=SRC70-6012&utm_source=googleshopping&utm_medium=cse
The author marked this model as their own original creation.