Prepare to have your heart melted by Robert Downey Jr. and his dapper 7-year old friend Alex. The Iron Man actor teamed up with bionics expert and Fulbright scholar Albert Manero to help give Alex, who was born with a partially developed right arm, an awesome 3D-printed bionic limb. As Alex grins at the very Iron Man-esque limb presented to him, Downey pulls out his very own bionic arm and the two test out the mechanical limbs together. Tears! Grab your tissues and prepare to weep watching the video above!

The actor, who plays engineering genius Tony Stark in Marvel's Avengers cinematic universe, wanted to help out after he heard about Manero's work with the volunteer group Limitless Solutions, an organization that donates low-cost 3D-printed limbs to children around the world.

According to Microsoft's The Collective Project, the arm cost a mere $350 to make. That's a drop in the bucket compared with the usual $40,000 price tag usually attached to prosthetic parts. "We were all bound to the belief that no one should profit from a child in need of an arm," Manero told Microsoft. This sparked the staff to pool their coffee money and donate the arm to Alex.

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