E3D v6 40mm Fan Duct and Extruder for NEMA-17 Motor

UPDATE:
By request I made a version compatible with the J-Head hotend for the Prusa-i3. There are two versions posted. The 'A' model has an upper opening to fit 2.0 mm I.D. PTFE and the 'B' model has an upper opening to fit 3.0 mm I.D. PTFE. I don't own a Prusa-i3 or J-Head so I'm basing this on dimensions that I've learned online and by those requesting this change. I hope it works for you. I suspect you will have to adjust the feed rate as the gearing for a direct extruder will be different