This is a replacement spool holder for the Makerbot Replicator 2X. It is designed to work with a cheap spool of ABS that you can buy from Amazon made by Zen Toolworks.
I printed both pieces with the flat face down out of ABS on the replicator 2x and super glued them together. Came out perfect. Used makerware slicer with medium quality, 6 skins and 20% infill. Works like a champ. These spools cost about 40% less than the spools on MakerBot website.