Retrofit kit

The automotive aftermarket is the secondary 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. According to a report by the International Trade Administration in the Department of Commerce, "Aftermarket parts are divided into two categories: replacement parts and accessories. Replacement parts are automotive parts built or remanufactured to replace OE parts as they become worn or damaged. Accessories are parts made for comfort, convenience, performance, safety, or customization, and are designed for add-on after the original sale of the motor vehicle."

The aftermarket encompasses parts for replacement, collision, appearance, and performance, including electric propulsion. 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.

The United States automotive aftermarket is estimated to be worth $318.2 billion (2013), contributing more than 2.3% to GDP. The aftermarket employs 4.2 million people who work at manufacturers, distributors, retailers and repair shops.

In the United States, online sales of aftermarket accessories have showed year over year increases over traditional brick and mortar stores. In fact, according to Hedges & Company, "Sales of auto parts & accessories continued to climb in 2015, and will continue the trend into 2016 to reach $7.4 billion dollars, posting around a 16% increase over 2015."

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Wikipedia