The product sold as a “hoverboard” did not hover. It was a self-balancing scooter with two wheels and a lithium-ion battery—hundreds of thousands of which were recalled in 2016 after reports of overheating, smoking, catching fire, and exploding. The future arrived, stayed firmly on the floor, and needed a fire-safety standard.
Source: U.S. Consumer Product Safety Commission
Image: МаратД / Wikimedia Commons, CC BY-SA 4.0.