Please note - if you are buying discs for the Walnut Hollow extruder adapter these 23mmm discs are a fraction too small and will fall out. The info with the extruder says the discs are 23mm when in fact they are slightly larger. I have someone testing 24mm discs in this adapter over the next couple of days, if these discs work, they will be listed on the website in a couple of days. Do NOT BUY 23mm discs for this adapter.