aftermarket

The automotive aftermarket is the secondary parts market of the automotive industry, concerned with the manufacturing, remanufacturing, distribution, retailing, and installation of all vehicle parts, chemicals, equipment, and accessories, after the sale of the automobile by the original equipment manufacturer (OEM) to the consumer. The parts, accessories, etc. for sale may or may not be manufactured by the OEM.
The aftermarket encompasses parts for replacement, collision, appearance, and performance. The aftermarket provides a wide variety of parts of varying qualities and prices for nearly all vehicle makes and models.
Consumers have the option of repairing their vehicles themselves (the "do-it-yourself" or "DIY" segment) or can take the vehicle to a professional repair facility (the "do-it-for me" or "DIFM" segment).
The aftermarket helps keep vehicles on the road by providing consumers the choice of where they want their vehicles serviced, maintained, or customized.

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