This was the prototype produced at the VA Innovation Creative Series in Rechmond on 7/29/15.  It was produced one of the stratasys machines that were graciously provided for the series.  The nut is inserted over the upper section of the coupler (With the male spline) and the upper section is bolted on to the existing socket using existing hardware.  The lower section is then attached to all necessary lower leg prosthetics.  Then the user need only mate the splines, (note that due to a unique shape in the spline the user doesn't have to worry about misaligning the prosthetic) and lower and tighten the nut to mate the coupler together.  

We did note that both the treads and spline pattern are too tight for production.  This will be addressed and improved in later versions.  Also the need for a lower section with the standard pyramid will be added.  Another feature that will need to be incorporated is a through hole throught he upper and lower section to allower for the use of thru-rod attachments.