Heater Box Rubber Plug

[Krateness]

In being an inpatient person, I accidentally tore one of these while removing them prior to my heater box being dipped. I’m not sure of their function but prefer to have them both back in place prior to installing the box back in the car. If anyone has an old beat up heater box that they’d be willing to pull on from and sell, please let me know.

I’ve attached a pic of the plug in talking about. There’s 2 per box and they sit behind the heater core. One on the top and one on the bottom.

Thanks
Andy