Circular fan duct for cr-10

I have found that with many circular fan ducts the nozzle is not even close to being centered...so I created this one.
In addition i tried designing the inside so that the filament is cooled equally from all sides.
Eventhough the ring is quite close to the nozzle (1cm to be exact) i have not expierenced any issues when printing with 200°C nozzle temperatur (i did not try more yet).