SummaryThis is a customized spool holder for the Prototype Supply brand filament, available from Toybuilder Labs (http://www.toybuilderlabs.com). Replicator: Use the "r2d" version. Replicator 2; Use the "r2e" version. Replicator 2x: Use the "r2e" version. This spool holder was created by editing the output of woale's Customizable Spool Holder for Replicator 2 -- http://www.thingiverse.com/thing:44906 to make the tongue fit into the slot on the Replicator. InstructionsTo print it, I suggest using a very high fill - at least 40%. If you are using thin layers, I suggest raising the solid layer thickness above the default 3 layers so that it comes out to 1 mm or thicker. Because this is a pretty big print, you will be fighting shrink and warp. If you can print PLA, I would recommend that. Also, to improve the strength of the spool holder, you might want to slightly under-report the filament diameter when slicing (or use any other techniques to fool the slicer into extruding plastic a little bit thicker). Finally, consider extruding the plastic a little hotter but slower than usual. YMMV. Once your print is done, break off the little bridge-helper tabs. To see the spools of ABS and PLA filament, in 12+ colors, which this spool holder was customized for, please visit http://www.toybuilderlabs.com/ - thanks!