David: When I was a kid I always played with Lego. I built cars, planes, motorbikes. But now, I built an arm.

Narrator: Meet David Aguilar.

David: My name is David Aguilar. I am from Andorra, and I'm 18 years old.

Narrator: When David was born, his right arm hadn't fully developed.

David: This is the … my right arm. When I was growing up, it was quite annoying because I received a lot of *commentaries (comments) like, 'Oh, you don't have a hand', or something like that.

Narrator: And while some would see this as a disadvantage, David is just a regular kid. He likes EDM. He goes by the name Hand Solo – get it?! He has an embarrassing dad, he goes to school …

David: This is my school.

Narrator: … and he can open doors with his Lego arm. So cool! Growing up, he was obsessed with Lego. So much so, he wanted to make it a part of him – literally.

David: I built my first prosthetic arm when I was nine years old, and I built it around my hand. It started (off) being a boat.

Narrator: Unfortunately, the Lego bricks weren't strong enough, and it wasn't for another nine years till he would try again.

David: This is MK1. This is Lego Technic. It's like the sophisticated part of Lego. I can do push-ups with this thing, so it's quite strong. When I first built the arm and it was fully functional, I went to the mirror and I was like, 'Uugh, er!'

Narrator: That model, the MK1, only took five days to build. Of course, like any good inventor, he got straight to work on an upgrade.

David: And this is MK2. It has a battery that works like a biceps, and it has this fishing cable that ties up in here. When I fix this to my shoulder, I can do this [demonstrates] and the arm closes. I can stop in the middle and move it by myself.

When I first brought this (into school), they were all really amazed because how can somebody create a hand out of Lego? I was a normal guy, and when I built the arm everyone was like, 'You're awesome, you're really smart.' They told me they are really proud to be my friends. It's amazing.