low profile ring cooler/circular fan duct for 5015 blower fan

This is my take on a ring cooler. All versions i found were too high for my application so i made my own. Works ok so far but i will make some changes. The holes are a bit too small at 3mm and blocking some of the airflow. The next Version gets 3,5-4mm holes.

Update: uploaded the 3.5mm hole version but haven't tested it yet.