This is a new finger for the Prosthetic Hand (progressive and independent finger movement) that is located here: http://www.thingiverse.com/thing:220942. 
This finger allows for more movement and should be used in place of the fingers on the previously posted hand. 
This design was created by Bob Roth from Tulsa, OK. and he has been gracious enough to share the design with our community of makers. 
This project is an extension of the work being done by Robohand, Ivan Owen, Jorge Zuniga, and the e-NABLE group. This work is being done in my lab at the University of Wisconsin Milwaukee. 
For more info see: 
http://frankieflood.blogspot.com/2014/01/prosthetic-hand-milwaukee-prt3-bob-roth.html 
http://frankieflood.blogspot.com/2014/01/prosthetic-hand-milwaukee-prt4.html 
Update: Ivan Owen added supports for Bob's finger design so this can be printed without supports. Ivan wrote the following: "I took the STL files and used design software to add in supports only where they are absolutely needed to print the finger. The resulting STL is attached. I tested it on my Makerbot Rep 2 using a 0.25mm layer thickness, 2 shells and 10% infill and no software generated supports. The result was a pretty nice print." 
In addition some of the e-NABLE group needed the files separated into smaller groups of parts so they could print on a smaller build platform. I have separated Ivan's file into two sets of parts. 
For more information on where to connect with people who can help someone in need with sizing, printing and/or assembly a mechanical hand please join the e-NABLE Google+ Community entitled, e-NABLE: 
https://plus.google.com/communities/102497715636887179986 
For more information and stories: 
http://enablingthefuture.org 
https://www.facebook.com/enableorganization