Sammy worked all summer on his invention, with help from a 3D printer.
MEDFORD TWP., New Jersey -- Sammy Salvano, 14, engineered a prosthetic hand for his friend, Ewan Kirby.
Ewan is missing most of the fingers on one of his hands, so Sammy worked all summer on his invention with help from a 3D printer.
It turns out, the hand is a perfect fit!
Ewan was able to pick up his mom's car keys for the very first time.
Sammy's mother, Sharon Salvano, says her son has been building for as long as she can remember.
Sammy, who is entering 8th grade, hopes to graduate from Drexel - like his grandfather - with an engineering degree.
His ultimate dream is to work for Elon Musk.