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

Accessories and ModificationsChevrolet Cobalt Owners Manual. Add-On Electrical Equipment
Notice: Do not add anything electrical to the
vehicle unless you check with your dealer/retailer
first. Some electrical equipment can damage the
vehicle and the damage would not be covered by
the vehicle's warranty. Some add-on electrical
equipment can keep other components from
working as the ...