50mm fan mount for Gregs Wade extruder

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????50mm????????thingiveres?????????????????????
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????GRABER i3??????????????????????????????
?????M3??????????????????????????????????

English:
I have some 50mm case fans, but I didn't find 50mm fan mount that can cool the hotend and the print at the same time.
so I make one.
It works great at my GRABER i3. I tested it for about 4 hours, and nothing wrong happened.
You need two M3 nuts and four nylon strips to assemble the fan to the mount and the mount to the ex