Shares of Tesla are spiking on Thursday afternoon, up 2% at $302.81, following a tweet from CEO Elon Musk announcing the release of a semi-truck from the company.

“Tesla Semi truck unveil set for September. Team has done an amazing job. Seriously next level,” Musk tweeted.

Tesla has been on a roll as of late, touching an all-time high of $313.73 on April 10, on its way to briefly becoming the most valuable car company in America.

Back on April 2, Tesla announced a record number of vehicle deliveries in the first quarter, up 69% year-over-year at 25,000 vehicles. The numbers sparked a massive rally in the stock, and prompted Musk to taunt short sellers of the stock, who have seen their losses pile up to more than $3 billion.

Shares of Tesla are up more 41.7% so far in 2017.