Iron Man and The Avengers star Robert Downey Jr. continues to put his superhero status to good use. Recently the actor, posing as robotics expert Tony Stark, presented a seven-year-old boy named Alex with a partially developed arm his very own Iron Man-inspired 3D-printed bionic arm.

The arm was created by a college student named Albert Manero, another real-life superhero, who heard about a man who had created a 3D-printed mechanical hand and decided he needed to be a part of it. He’s been doing great, truly inspirational work ever since, building and donating low-cost 3D-printed bionic limbs to kids all around the world.

You can read more, see videos of Downey Jr. presenting the arm to Alex and the work Albert is doing, and find out how you can get involved below.