2204 propguard

As I am a total beginner with drones, I designed some propguards for my 250 ZMR China clone quadrocopter. It comes with 2204 2300KV motors, so I checked the datasheet and made the mounting holes accordingly.
I intentionally didn't make the guard too thick, because I wanted it to break before parts of the frame break, especially the arms. Each weights 10 gramms.
I had several testflights with the current version 3.1, the propguards work fine and saved me some propellers.

I hope you enjoy them, and If there is need to make anything better, don't hesitate to leave a comment.

EDIT:
The guard has a diameter of 156mm, thats appx. 6''.
I'm flying with 5030 propellers.