The Coat Glossiness Render channel is analogous to the Reflection Glossiness Render Channel, with the main difference being that all Coat render elements can be subtracted from the main back-to-beauty composite, graded, and added back in.

UI Path: ||V-Ray Node Editor|| > World > Render Channels > Advanced > V-Ray Coat Glossiness

See the Render Channels page to find out where you can find these properties.

Channel Name – Customizable name for the render channel.

Enable Deep Output – Specifies whether to include this render channel in deep images.

Filtering –  Applies an image filter to this channel.