The Replacement Vacuum Pump for Dometic VacuFlush RV Toilet - 12V # DOM33FR comes with everything that is pictured in the photos on the product page. I do believe you're referring to one of the connections for the pump that is threaded (shown in attached photo), which is included. view full answer...
It depends on the part. For example, the Valterra frame and glass you were looking at, part # A77051, does not include the seal. It's just the frame, glass, and mounting hardware.
On the other hand, part # LC363370 from Lippert is the frame, glass, and seal but no hardware is included.
Both parts I referenced are 12 by 21 inch glass. view full answer...