O'Reilly Automotive, Inc. is a specialty retailer of automotive aftermarket parts, tools, supplies, equipment, and accessories in the United States (U.S.), selling its products to both do-it-yourself (DIY) and professional service provider customers. Its stores carry various product lines, including new and remanufactured automotive hard parts and maintenance items, such as alternators, batteries, brake system components, belts, chassis parts, driveline parts, engine parts, fuel pumps, hoses, starters, temperature control, water pumps, antifreeze, appearance products, engine additives, filters, fluids, lighting, oil, and wiper blades and accessories, such as floor mats, seat covers, and truck accessories. Its stores offer services and programs, including battery diagnostic testing; battery, wiper, and bulb replacement; a loaner tool program; custom hydraulic hoses, drum and rotor resurfacing, electrical and module testing, used oil, oil filter, and battery recycling; and others.