public int rawRenderQueue { get; }

This property returns the render queue override value of this material. The value returned is -1 if no override has been specified (i.e. the actual renderQueue value used for rendering will be Shader.renderQueue), or a custom value in [0..5000] range if set.

For purposes of getting the actual render queue value used for rendering, refer to Material.renderQueue.

Additional Resources: Material.renderQueue, Shader.renderQueue, RenderQueue enum, subshader tags.