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Most of the time, people return products because they’re unhappy with their experience. Maybe the memory foam mattress got too hot, the bicycle seat wasn’t comfortable or the TV proved too big for the living room. And perhaps that pricey hot tub simply wasn’t worth the three paychecks, after all.

Unfortunately, other products wind up back in manufacturers’ factories for another reason altogether: the dreaded product recall. Companies most often recall products to address safety issues, like faulty air bags or contaminated food. When handled well, recalls can help corporations reinforce customer trust and loyalty. When handled poorly, they can turn into a PR disaster.

With this in mind, FindTheCompany set out to catalog the 25 biggest product recalls of 2015. To assemble the list, we curated statistics for each recall based on CNBC’s reporting up through Dec. 3, 2015. We then ranked the list by the total number of units recalled. For each recall on this list, we’ll provide context on the specific product flaw, model defect or food contamination, and where available, detailed info on the affected units.

#25. Hyundai Sonata Faulty Engine Parts

Number of Units: 470,000 cars
Date: Friday, Sept. 25

Hyundai reported “faulty engine parts” in documents submitted to the National Highway Traffic Safety Administration, but there were no reported accidents or injuries as a result of the issue.

#24. Volkswagen Emissions Scandal

Number of Units: 482,000 cars
Date: Friday, Oct. 2

After Volkswagen was caught cheating on emission tests — the company built software that made its cars seem more environmentally friendly during tests — the Environmental Protection Agency ordered the recall of nearly half a million cars.

#23. Sanderson Farms Chicken Contamination

Number of Units: 500,000 pounds of chicken
Date: Tuesday, Oct. 6

According to the U.S. Department of Agriculture, about half a million pounds of Sanderson Farms chicken products were potentially contaminated with metal, triggering a recall.

#22. Fiat Chrysler Ignition Switches

Number of Units: 702,578 cars
Date: Monday, Mar. 9

Fiat Chrysler had to recall over 700,000 SUVs and minivans after it discovered that the ignition switches could turn off the engine without warning.

#21. GM Lift Gate

Number of Units: 780,000 cars
Date: Friday, July 10

General Motors had to recall 780,000 SUVs after it discovered a flaw in the rear power lift gates, which could fall unexpectedly and hit people.

#20. Fiat Chrysler Brakes and Air Bags

Number of Units: 894,000 cars
Date: Friday, Oct. 30

Due to an issue with anti-lock brakes and air bag deployment, Fiat Chrysler had to recall nearly 900,000 SUVs.

#19. Trek Bicycle Quick Release

Number of Units: 998,000 bikes
Date: Thursday, Apr. 23

Several riders were injured due to a flaw in quick-release levers on Trek Bicycle’s forcing the company to recall nearly 1 million bikes.

#18. SABMiller Broken Glass

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Number of Units: 1.03 million bottles of beer
Date: Dec. 3, 2015

Beer giant SABMiller discovered that some bottles contained loose pieces of broken glass, forcing the company to recall more than 1 million units.

#17. Ram Truck Steering Wheel Defect

Number of Units: 1.06 million trucks
Date: Thursday, Sept. 10

Fiat Chrysler had to recall more than 1 million Ram trucks due to a steering glitch that would sometimes deploy the air bag unnecessarily and without warning.

#16. Mazda Ignition Switches

Number of Units: 1.2 million cars
Date: Friday, Oct. 23

Mazda reported using “too much grease” on ignition switches in the ’90s, increasing the risk of fire on some decades-old models. It’s an example of how recalls can happen at just about any time, even 15 years after release.

#15. Toyota Air Bags

Number of Units: 1.37 million cars
Date: Tuesday, June 16

Takata makes air bags for several car manufacturers, including Toyota. According to the recall, the Takata air bags could potentially expand with too much force, potentially causing metal shards to fly out at passengers. Toyota was one of many affected manufacturers.

#14. Honda Air Bags

Number of Units: 1.39 million cars
Date: Monday, June 15

Another victim of the Takata air bag defect, Honda also had to recall more than 1 million cars.

#13. Fiat Chrysler Hacking Bug

Number of Units: 1.4 million cars
Date: Friday, July 24

A vulnerability in some of Fiat Chrysler’s radios allowed hackers to turn off a car’s engine as it drove.

#12. GM Oil Leak and Fire Hazard

Number of Units: 1.4 million cars
Date: Tuesday, Oct. 27

General Motors realized that hard braking could result in oil leaks, which in turn could cause a fire hazard.

#11. Toyota and Nissan Air Bags

Number of Units: 1.56 million cars
Date: Wednesday, Nov. 25

More Takata air bag victims, this time in May.

#10. Toyota Air Bags

Number of Units: 1.6 million cars
Date: Wednesday, Nov. 25

Yet another wave of recalls as a result of the Takata air bag defect — in this case, just affecting the Japanese models.

#9. General Mills Cheerios

Number of Units: 1.8 million boxes of cereal
Date: Monday, Oct. 5

General Mills labeled nearly 2 million Cheerios boxes as “Gluten-free,” despite the fact that the product contained wheat.

#8. Aspen Foods Chicken Contamination

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Number of Units: 1,978,680 pounds of chicken
Date: Thursday, July 16

After a possible salmonella chicken contamination scare, Aspen Foods was forced to recall nearly 2 million pounds of chicken.

#7. Kraft Heinz Turkey Bacon

Number of Units: 2 million pounds of turkey bacon
Date: Wednesday, August 26

Kraft Heinz was forced to recall millions of pounds of Oscar Mayer turkey bacon after several customers reported getting sick, even when eating the bacon before the “best when used by” date.

#6. Honda Air Bags

Number of Units: 4.5 million cars
Date: Thursday, July 9

Takata air bags strike again for a fresh range of Honda models.

#5. Toyota and Nissan Air Bags

Number of Units: 4.94 million cars
Date: Wednesday, May 13

Another escalation of the Takata air bag fiasco.

#4. Toyota Power Windows

Number of Units: 6.5 million cars
Date: Wednesday, Oct. 21

Toyota explained that workers had used lubricant inconsistently on some cars windows, creating the possibility that a window power switch could short circuit, overheat and cause a fire.

#3. Kraft Mac & Cheese

Number of Units: 6.5 million packages
Date: Tuesday, March 17

Kraft was forced to recall millions of Mac & Cheese packets after they discovered that some could contain scraps of metal.

#2. Volkswagen Emissions Scandal

Number of Units: 8.5 million cars
Date: Thursday, Oct. 15

Further fallout from the VW emissions cheating scandal, affecting more than 8 million cars across the European Union.

Note that the EPA has yet to formally require the recall.

#1. Takata Air Bags Overall

Number of Units: 34 million air bags
Date: Thursday, Aug. 11

Taken all together, the Takata Air Bags defect forced a recall of 34 million air bags, by far the largest recall event of 2015.

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