Elon Musk鈥檚 Boring Company has racked up 15,000 pre-orders for its US$500 flamethrower, which the billionaire inventor has touted as insurance against a zombie apocalypse.

It sounds like a tongue-in-cheek invention, but the black-and-white, shotgun-sized flamethrower is legitimately for sale 鈥 and interest has been red-hot.

Musk announced the flamethrower on social media Jan. 27, and has been updating his pre-order numbers ever since. He tweeted that sales had surpassed on Tuesday morning, with only 5,000 remaining.

The says it will begin shipping in spring, with refunds available for any international customers who think twice after seeing the additional shipping and customs fees that might be required.

The listing also says the flamethrowers are not to be used on 鈥淏oring Company decorative lacquered hay bales or Boring Company dockside munitions warehouses.鈥

Musk founded the Boring Company in December 2016 as a tunnel-drilling firm. He also previously founded Tesla, SpaceX and PayPal鈥檚 predecessor.

The geeky billionaire has been cracking flamethrower and zombie jokes on Twitter for days.

鈥淲hen the zombie apocalypse happens, you鈥檒l be glad you bought a flamethrower,鈥 he on Saturday. 鈥淲orks against hordes of the undead or your money back!鈥

He also offered a brief word of caution, saying: 鈥淥bviously, a flamethrower is a super terrible idea. Definitely don鈥檛 buy one鈥 Unless you like fun.鈥

 

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Use of a flamethrower is extremely dangerous outside zombie apocalypse situations.