This is a replacement for "Portal_Gun_White_Left_Shell_Slice_6.stl" in thing #26027. The original file specified a triangle count of 6964 triangles, but reached end of file after 6963, so was an invalid STL format. Some tools would refuse to read it; others would read it, but you'd have a hole or perhaps a corrupted final triangle. This is identical to the original file, but with the missing triangle added to the end.Get all the files from http://www.thingiverse.com/thing:26027 and then replace the file "Portal_Gun_White_Left_Shell_Slice_6.stl" with this one. Follow all the instructions & cautions on the original.