This is Threaded Filament Dust Filter - Replicator 1,2 & 2X by ppyromann with instructions to make a filament colorizer.Print the filter, put in a sponge (I used a wedge shaped makeup sponge cause that's what I had laying around), fill with alcohol based ink. I got the alcohol based ink from Dick Blick http://www.dickblick.com/products/spectrum-noir-marker-ink-refills/ . You can make your own colors if you get the three primary colors (red, blue, yellow) and mix them, plus black. Assemble the filter but don't screw it together, put the filament and sponge in the filter, fill it up with ink, and screw it together. I needed to ream out the barrel a little because the hole was pretty tight and pulled the ink back off the filament. When I reamed it out so there was a little extra room, the ink stayed on the filament. Note: the print file is not changed at all from ppyromann's file. All of the credit for the design of the original filter goes to ppyromann. I just get the credit for the alcohol ink idea, which is based on all of the ink colorizers using Sharpies.