Here is a custom 30.5mmx30.5mm adapter for the Piko BLX 20mmx20mm from Furious fpv.
It is printed in TPU (ninjatek) to protect the flight controller from vibration and shock.
Store EU:
https://www.drone-fpv-racer.com/piko-blx-micro-flight-controler-furious-fpv-980.html
https://www.facebook.com/Microdure/
Creative Commons Attribution Noncommercial No Derivatives
