WARNING: This page is about a different car, the 2020 Buick Regal and 2019 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
Courtesy of GENERAL MOTORS COMPANY
Callout
Component Name
1
Vacuum Pump Pipe Bolt [2x]
2
Vacuum Pump Pipe
3
Vacuum Pump Pipe Seal Procedure Discard seal, it is not reusable.