One more sponge-box for Replicator 2!!!!Normally, just print the STL file. Cut a kitchen sponge at the size of the box, cut a hole in the sponge to let the filament go thru, close the box, put it on the back of the Rep2 instead of the filament guide tube, and print with a nice clean filament !!!The box can be a bit tricky sometimes to close, depending on the thickness of your sponge.The small hole on the top of the cover is to add some water from time to time, to keep everything smooth. Use a straw, works well for me.