It doesn't appear to be a part but rather a sketch (and not complete except for pcb at that). If you download the SMD_Relay_Board.fzz file and open it in fritzing you will get an incomplete breadboard and schematic view and an apparantly complete pcb view (pcb view may be all the author needed). You can export the gerbers and have a board made as it stands. If you need breadboard or schematic you would need to place and route them following the rats nest lines created from pcb view to complete the other 2 views if you need them. There don't appear to be any custom parts in it (as there is no temp parts bin when I load it) so all the parts are available in the core parts bin. Which part are you interested in exporting?
Peter