The community, called e-NABLE, which is largely based the United States, brings together volunteers using 3D printers and 3D design software to make the prosthetics.

Recipients include children and adults who are missing fingers, hands and wrists. They receive the prosthetics for free.

One young boy, called Keiran from Watsonville in the U.S. is the recipient of one of the hands. He was born with congenital disorder Amniotic Band Syndrome which means he has no fingers on his right hand.

He suffered bullying at school and couldn't perform simple tasks.

But in a video produced in partnership with e-NABLE he said he loved his new hand because it allowed him to pick things up, and people at school were now friendly towards him.

The e-NABLE community was founded in July 2013 by Jon Schull, in the hope of providing prosthetics for people who could not afford to spend thousands of dollars. Its membership is now over 5,500 people.

Keiran was 11 years old when Andreas Bastian, a 3D printing research scientist at Autodesk Pier 9, started working with him in December 2014.

Bastian spends time responding to feedback from Keiran, his parents, designers and other users.

Keiran shares sketches of ideas with Bastian and points out where something feels uncomfortable.

Hands need to be custom-made according to each person's requirements. The prosthetics can also be cheaply updated as children grow.

In future, e-NABLE aims to address other upper limb difficulties, developing new designs to deal with them. Bastian estimates roughly 1500 hands have been produced since the community's conception in 2013.

