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...
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...