For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningReporting Safety Defects to the United States Government
If you believe that your vehicle has a defect which could cause a crash or could
cause injury or death, you should immediately inform the National Highway Traffic
Safety Administration (NHTSA) in addition to notifying General Motors.
If NHTSA receives similar complaints, it may open an investig ...
Installation Procedure
Clean and prepare the attaching surfaces for welding.
Position the roof rear header panel (1) on the vehicle.
Verify the fit of the panel.
Clamp the roof rear header panel into position.
Spot weld accordingly as noted from the original panel.
Apply the sealer ...
Heated Front Seats
WARNING
If you cannot feel temperature change or pain to the skin, the seat heater
may cause burns. To reduce the risk of burns, people with such a condition should
use care when using the seat heater, especially for long periods of time. Do not
place anything on the seat that insulates again ...