SAN FRANCISCO (CBS SF) — If you’re traveling by air this holiday season, don’t pack your hoverboard.

Several airlines have issued bans on the popular, self-balancing scooters due to concerns they may spontaneously ignite.

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Hoverboards are powered by lithium batteries, which when defective, can overheat, catch fire and explode. The U.S. Consumer Product Safety Commission has launched an investigation following several incidents.

So far, Delta, American, United, Alaska and Southwest Airlines no longer allow hoverboards or similar devices in checked luggage, or as a carry-on.

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“As cool as they [hoverboards] are, there’s one big problem: they are not safe to transport on an airplane,” Alaska Airlines said on its blog. “Internal short-circuits can occur with lithium ion batteries, which can then lead to a “thermal runaway” where the battery overheats and bursts into flame.”

There are concerns some Chinese-manufactured hoverboards have knock-off lithium batteries that do not meet U.S. standards.

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Last week, Amazon sent a notice to manufacturers demanding safety documentation. Over the weekend, the online retailer pulled the sale of nearly all of the hoverboards on its website.