More than 500,000 hoverboards are being recalled because of fire hazards that pose the risk of injuries, according to the U.S. Consumer Product Safety Commission. The recall involves hoverboards from eight manufacturers/importers that are made with lithium-ion battery packs as well as 4,300 from Overstock.com and 1,300 from a store in Pennsylvania. Amazon.com is not listed in the recall, but in February, the online giant worked with the CPSC to offer refunds to any customer who wanted to return hoverboards purchased on the site. Hoverboards by Swagway make up more than half of those recalled -- 267,000.