The Boring Company is a tunnel construction business founded in 2016 to provide the infrastructure for an underground Hyperloop.
Musk suggested selling flamethrowers for $500 each as a method of raising funds for the new business venture.
The company claims to have sold 20,000 already – bringing in around $10m (£7.5m) in revenue.
The first 1,000 of these flamethrowers were handed out to customers at the company’s offices in Hawthorne, California this weekend.
Tweeting from Hathorne, the Tesla and SpaceX chief executive added: “Due to recent regulatory/customs rules enacted to inhibit transport of anything called a Flamethrower, we have renamed our product: ‘Not-a-Flamethrower’.”
The guns work more like large blowtorches rather than actually spewing flames long distances.
Musk posted the terms and conditions for the “Not-a-Flamethrower” on Twitter too, noting the company’s inspiration from the Dr Seuss book Green Eggs And Ham:
I will not use this in a house
I will not point this at my spouse
I will not use this in an unsafe way
The best use is creme brulee….
The announcement of the flamethrower sales followed the company selling roughly 50,000 hats for $20 each, raising $1m in revenue.
As of April the company said it had raised over $112m in equity, 90% of which came from Musk himself.
The sale was announced on Twitter, where Musk remains an active user after deleting the official Facebook pages for his SpaceX and Tesla brands amid concerns over the security of the social network.
Musk’s presence on the platform has led to scammers impersonating him to con Twitter users out of tens of thousands of pounds a day, a Sky News investigation revealed in March.
Tesla shares plummeted earlier this year when the CEO called an analyst a “boring bonehead” in response to a question about the company’s record net loss.