Could someone please help me identify what this vent is called and what the purpose is? I tried searching Google and can't find anything. A lot of stoves only have the slider vent on the bottom, so I'm not sure what the purpose is and doesn't seem to make a difference whether it is open or closed.
Thank you!
![Part Identification Part Identification](https://www.hearth.com/talk/data/attachments/290/290422-89612fd23e02e46af21863dcab8dc618.jpg)
Thank you!
![Part Identification Part Identification](https://www.hearth.com/talk/data/attachments/290/290422-89612fd23e02e46af21863dcab8dc618.jpg)