In celebration of the success of his Boring hat sales, Elon Musk is stepping up the sale of Boring Company branded items. Musk has been tweeting each milestone of Boring Company hat sales and on Sunday, he said the company had successfully sold 30,000 of them. So what’s next? Once the company sells 50,000, the next item will be “The Boring Company flamethrower,” Musk tweeted.

He then tweeted again saying that a flamethrower is a bit “off-brand, but kids love it.” When someone commented and said that kids love flamethrowers made by Musk because they’re “super safe” he replied, “Safest flamethrower ever.

Each of Musk's hats sells for $20. The price includes taxes and shipping and buyers get a signature Boring Company hat. They’re somewhat limited, only 50,000 will be sold, and more than 30,000 of them are already gone. Musk posted a photo of the hat on his Instagram as well and said again that the flamethrower was next.

The proceeds from the hat sales go right to the Boring Company, for more boring. The goal of the company is to create a network of tunnels under cities, starting with Los Angeles, that will help alleviate traffic and speed up travel. Once the tunnels are completed, Musk said they’ll take users from Westwood to LAX in five or six minutes. The tunnels are collectively called the Loop, a high-speed underground public transportation system, according to The Boring Company. The tunnels will be accessible by a lift designed to carry an entire car underground, that Musk and his company have already created.

Digging started in June in California by the machine that Musk named Godot. Musk has said he’s been searching a way to fund the tunnels, which is where the hat sales came in to play.

In July, Musk posted a video of the car elevator lowering a Tesla down into the tunnel that had been in the works. The elevators would be along the side of the road for drivers to glide onto and down into the tunnels for traveling.

Musk posted a photo of one section of the tunnel to Twitter in October that showed what appeared to be cement-clad tunnel with what looked like tracks headed down the center. The lift and the tunnel are built in Hawthorne, California, where Musk’s companies are headquartered. Currently, project expansion to Los Angeles, the East Coast, and Chicago, are in the early stages of development and are still pending approval.