The U.S. Consumer Product Safety Commission has issued urgent warnings covering four separate brands of heated insoles, all sold primarily through Amazon, after receiving 54 reports of fires, explosions, or thermal incidents and at least 46 burn injuries. The products, marketed under the names COOWALK/COOWALI, METASONO/MEATSONO, Meisinuo, and iHeat, share a common and alarming defect: their internal lithium-ion batteries can explode and ignite even when the insoles are switched off. Roughly 7,400 units reached consumers between 2022 and 2026, and the agency is telling every owner to stop using them immediately.
Four brands, one recurring battery failure pattern
The scale of the problem has grown quickly. The CPSC warning on COOWALK/COOWALI insoles covers approximately 6,000 units sold on Amazon.com and GearTrade.com from August 2022 through May 2026. The agency documented 26 reports of fires, explosions, or thermal incidents tied to those insoles and at least 23 burn injuries. Separately, approximately 1,372 Meisinuo heated insoles sold on Amazon.com from August 2023 through December 2024 generated 17 thermal incidents and at least 15 burn injuries, including serious second-degree burns.
The METASONO/MEATSONO insoles, described as navy or multicolor with “METASONO” printed on both sides, were sold on Amazon.com and eBay.com from July 2023 through July 2026. The CPSC issued a parallel warning for those products using identical hazard language about batteries exploding when the device is off. An earlier 2025 warning covered iHeat insoles, manufactured by Zhangfengqing doing business as iHeat and also sold on Amazon, which produced eight burn injuries, some second- or third-degree.
What ties these cases together is the specific failure mode. In each warning, the CPSC used the same core finding: the internal lithium-ion battery can explode and ignite independent of whether the user has activated the heating function. That detail separates these incidents from typical overheating complaints. A device that can catch fire while sitting in a closet, a shoe, or a bag presents a risk that extends well beyond active use.
Clinical evidence and a longer regulatory trail
The CPSC warnings are not the only record of harm. A peer-reviewed case series published in the Journal of Burn Care and Research documented full-thickness burn injuries from heated insole explosions treated at a burn center between December 2023 and February 2024. Full-thickness burns, formerly called third-degree burns, destroy the entire depth of the skin and often require surgical intervention. The clinical documentation supports the severity described in the CPSC reports and confirms that thermal runaway in these devices can cause lasting physical damage.
The pattern also has precedent in adjacent product categories. In 2019, the CPSC recalled Tech Gear 5.7 Performance Heated Socks after reports of batteries overheating, melting, or igniting. Those socks were sold on Amazon.com from September through November 2018. The recurrence of the same hazard, lithium-ion batteries failing violently in low-cost heated footwear products sold through major online marketplaces, suggests the problem is structural rather than isolated to any single manufacturer.
Thermal runaway occurs when a lithium-ion cell enters a self-reinforcing cycle of rising temperature that the battery’s protection circuitry cannot interrupt. In well-engineered consumer electronics, multiple layers of protection, including current limiters, thermal cutoffs, and cell-level fuses, prevent this chain reaction. The fact that these insoles ignite even when powered off points to a failure at the cell level or in the protection circuit itself, meaning the battery does not need an external trigger to become dangerous.
Why low-cost wearables are especially vulnerable
Heated insoles occupy a particularly risky niche. They are worn directly against the foot, often inside insulated boots designed to retain heat. That environment limits heat dissipation and concentrates any thermal event against skin and soft tissue. At the same time, many of these products are marketed at low price points, which can incentivize manufacturers to use cheaper cells or omit robust protection components that add cost and bulk.
Unlike laptops or smartphones, which must pass through multiple layers of brand oversight and carrier or retailer testing, many heated insoles are produced by small manufacturers and sold through third-party storefronts on large online marketplaces. The CPSC’s warnings for Meisinuo, COOWALK/COOWALI, and METASONO/MEATSONO all describe products sold primarily through Amazon, underscoring how easily hazardous designs can reach a national audience without traditional brick-and-mortar gatekeeping.
Wearable heating products also tend to be seasonal purchases, often bought quickly in response to cold weather or outdoor work needs. Consumers may focus on warmth and price rather than on electrical safety certifications or brand reputation. Listings can emphasize long battery life and high maximum temperatures, features that, if achieved without adequate safeguards, may increase the risk of catastrophic failure.
What affected consumers should do now
The CPSC is unequivocal: anyone who owns heated insoles covered by these warnings should stop using them immediately. Because the batteries can ignite even when switched off, the safest course is to remove the insoles from footwear, avoid charging them, and store them in a nonflammable area away from combustible materials until they can be disposed of properly.
Consumers should check past Amazon and eBay orders for the brand names COOWALK, COOWALI, METASONO, MEATSONO, Meisinuo, and iHeat, paying close attention to purchase dates from 2022 onward. Product images and descriptions in order histories can help confirm whether a pair of generic-looking insoles matches those described in the CPSC notices. If there is any doubt, erring on the side of caution and discontinuing use is prudent given the severity of reported injuries.
Proper disposal is important. Local waste authorities often provide guidance on handling damaged or recalled lithium-ion batteries, and many communities operate battery collection programs through recycling centers or hazardous waste facilities. Tossing heated insoles with embedded batteries into regular household trash can create downstream fire risks in garbage trucks or transfer stations.
Broader lessons for battery-powered gear
The heated insole incidents offer a cautionary example for the wider category of battery-powered wearables, including heated gloves, vests, and socks. Consumers can reduce risk by favoring products from established brands with clear contact information, documented safety testing, and detailed manuals that describe charging limits and storage conditions. Independent safety marks, while not foolproof, indicate at least some level of third-party review.
Simple handling habits also matter. Avoid charging any wearable heating device unattended or overnight, and discontinue use if the battery pack becomes swollen, unusually hot, or emits a chemical odor. Devices that continue to heat after being switched off, or that shut down unexpectedly, may signal internal faults that could precede more serious failures.
For regulators and marketplaces, the cluster of insole cases highlights the need for more proactive oversight of small electronics that embed lithium-ion cells directly against the body. Better pre-market screening, clearer labeling of battery specifications, and rapid information-sharing when early incidents occur could help prevent similar patterns from repeating in the next wave of low-cost heated products. Until such safeguards are routine, the safest approach for consumers is to treat bargain-priced, battery-powered footwear with skepticism-and to heed CPSC warnings promptly when they appear.
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*This article was researched with the help of AI, with human editors creating the final content.
