CTC I3 Cooling Duct for stock extruder

Update1:
Redesigned the flansh because i missed out one screwhole, rounded the Corner so air get smoother trough and widend the holes and a long hol for better removing the supports.
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Still in designing but i want your suggestions what i should changen or maybe different methods to attache it
atm it should get attached with 3 M3x45mm bolts but i just had the x40mm so i did it the dirty ziptie methode just to test

if someone can make one and tell me what would make it more effi