The internet is full of stories about some student 3D printing a hand for a classmate or even themselves with a desktop 3D printer. Amazing to be sure, but for the most part those 3D printed hands offer limited function. Which might lead some to think that 3D printing is not really useful here.

In the hands of engineers, however, a 3D printed hand can do interesting things, like throw a baseball. University of Navada Las Vegas (UNLV) engineers heard the story of 7-year old Hailey Dawson who had a special dream—she wants to throw the first pitch at every major league baseball stadium. But Hailey has Poland Syndrome, a birth defect where she’s missing three fingers on her right hand. So the UNLV engineers 3D printed a hand that helps her throw a baseball.

The story hit Twitter, and with the help of MLB, Hailey is on her way to achieving her dream.