tender details

[bob kaplan]

At the "fill-end" of both the K-27 and C-19 Bachmann models the are two circles surrounded by six "dots."  The circles are actually holes that go into the tender.  Does anyone know and able to tell me what they are in the real engines.   If the are actually holes, could the be for adjusting the air pressure in the tender as the water is used?   Thanks for the help?

[edmc]

These holes on the models at the rear are what would be on full size tenders to let water on the deck from filling the tender to run into the tank and also to let air into the tank as the injectors suck the water out when filling the boiler..