When doing replacement or upgrading on 2016 – 2019 Buick Envision with capsule halogen headlamps HID, the bulb size guide is necessary for you to take the reference.
Jump to corresponding car model with the catalog bellow.

High Beam and Low Beam Headlight 2016 – 2019 9012
Front Fog Light 2016 – 2019 H8/H11/H16
Back Up Light 2016 – 2019 921
Front Turn Signal 2016 – 2019 7444NA
License Plate 2016 – 2019 194
Parking Light 2016 – 2019 7443NA
Rear Turn Signal 2016 – 2019 7440NA
High Beam and Low Beam Headlight 2016 – 2019 D3S
Front Fog Light 2016 – 2019 H8/H11/H16
Back Up Light 2016 – 2019 921
Front Turn Signal 2016 – 2019 7444NA
License Plate 2016 – 2019 194
Parking Light 2016 – 2019 7443NA
Rear Turn Signal 2016 – 2019 7440NA