Billionaire Elon Musk on Thursday closed orders for his latest novelty product after selling a total of 20,000 flamethrowers at $500 (€402) a piece.

Musk's tagline for the impromptu fundraising scheme had been "Guaranteed to liven up any party." The sale raised $10 million for his high-speed tunnel venture "The Boring Company."

The sale of flamethrowers came on the back of a similar fundraising campaign in which Elon Musk shifted 50,000 Boring Company hats.

What's next?

"When the zombie apocalypse happens, you'll be glad you bought a flamethrower," tweeted the man behind Tesla and SpaceX. "Works against hordes of the undead — or your money back."

Musk added each flamethrower would come with something to put out a fire.

The latest fundraising plan came at a time when financial analysts and investors in e-carmaker Tesla are wondering if Musk would have to seek billions more in resources as it struggled to meet promises on its Model 3 production.

hg/jbh (dpa, Reuters)