Tesla’s chief executive, Elon Musk, has appeared to joke about whistleblowers on Twitter in the wake of high-profile lawsuits against the electric carmaker brought by current and former staff.

The billionaire urged his 65 million Twitter followers to “Blow the whistle on Tesla!” and included a link to a branded “Cyberwhistle” for sale in the company’s online shop.

Despite being priced at $50 (£38), the stainless steel whistle had apparently sold out online within minutes, with many of Musk’s Twitter followers tweeting to say they had bought the item, which is shaped like Tesla’s futuristic Cybertruck vehicle.

In a follow-up tweet, the 50-year-old, who is also the owner of Space X, told his followers: “Don’t waste your money on that silly Apple Cloth, buy our whistle instead!”, referring to Apple’s recently unveiled polishing cloth, which is on sale at the firm’s UK online store for £19.

Tesla has faced several lawsuits in the US in recent months from current and former employees, some of whom have complained of harassment while at work.

A federal court in California ordered Tesla in October to pay almost $137m in damages to a black former employee who said he endured racial abuse while working at the firm’s main factory in Fremont.

Owen Diaz, a former contracted elevator operator, had complained of racial abuse while working at the plant between 2015 and 2016.

In November, a worker at Tesla’s main California factory filed a lawsuit alleging rampant sexual harassment and lack of support from supervisors when complaints were raised.

Jessica Barraza said she was regularly propositioned by colleagues and had to endure inappropriate touching at the Fremont plant. She said the firm’s human resources department had not responded to complaints she filed with them in September and October.

Musk, whose personal worth is estimated at about $271bn, has a track record of courting controversy through his tweets, his preferred means of communication. In recent months he has promoted bitcoin and other cryptocurrencies, polled Twitter users over whether to sell some of his Tesla shares, and also mocked the US Senator Bernie Sanders over comments about taxing the wealthy.

Some of his tweets have got him and his company into trouble. The US securities watchdog warned Tesla last year that Musk had twice violated a settlement requiring his tweets and material public communications to be pre-approved by company lawyers, as first reported by the Wall Street Journal.

The Cyberwhistle is made from “medical-grade stainless steel”, according to the Tesla website, and described as being “inspired by” the Cybertruck, an electric pickup truck made from stainless steel used in rockets.

The armoured vehicle was revealed two years ago, in November 2019, with Musk tweeting only days later that the company had received 150,000 orders.

Musk has told Tesla investors that Cybertruck production will begin in 2022. However, in recent days he complained of supply chain problems in response to a tweet requesting an update on Cybertruck delivery.