This is a replacement for the plastic mount for the duct fan on the left side of a Replicator2 extruder. It is a direct bolt on replacement which should be stronger than the stock mount. It also holds the cable bundle much more securely than the stock part. There is a hole for a small zip-tie to pass through and positively secure the cable. I printed it out at 50% fill and it took an hour. v2 file does not require rafts or supports so there is no cleanup. Just print with the face that mates with the fan on the platform and then install! The version with "No Tube Holder" is only for a cleaner look and better access if you have an extruder which has a guide tube holder built in (3in1 Universal Extruder Upgrade shown).I sliced this model using the latest Makerware. I used PLA on the high quality setting (5 shells, 20% fill, no rafts/supports). Place the fan mounting surface on the platform and print and install. Having the guide tube mount removed (because it is present on the extruder) is a huge time savings when you have a clog. You can unbolt the extruder and slide it up the filament without having to unload. Also, it gives clear access to the thermal barrier tube if you need to remove burnt material with a toothpick/drill bit by and. Also, if you rotate the stepper motor so the wiring connector is towards the left side, it is a much cleaner look... very neat and tidy.