This cast is 1 of 2.  Sternberg owns the other.  First discovery of this species.  Discovered in 2003.  When making the 3rd cast the original was destroyed so there will never be another like it.  This is the most complete find of a Nyctosaurus to date.  If you google nyctosaurus this cast is on the second page in google images.

http://www.oceansofkansas.com/pteranodon.html

about 3/4's down this page is this cast.  

VERY neat and rare piece, do a little research and you'll quickly find how rare this piece is