David Aguilar, a nineteen-year-old from Andorra, Spain was born with a rare genetic condition that caused him to lose his right forearm. He is currently studying bioengineering at the Universitat Internacional de Catalunya (University International of Catalunya) in Spain and already using his fourth prosthetic arm model. His favorite toy, the Lego bricks, had become the building material for all of his artificial arms and were the building blocks for his first arm that he made at the age of nine.

At eighteen, he proudly displayed his first fully functioning robotic arm. All of his arms can do everything a real arm can do, like picking things up and bending at the elbow.

A small motor is inside of the elbow joint and whirrs as the arm flexes. After college, David dreams to create affordable prosthetic solutions to the disabled.

“I would try to give them a prosthetic, even if it’s for free, to make them feel like a normal person, because what is normal, right?” David said, in an interview with Reuters.