Queen Cell Cage - for plastic foundation

I currently use mostly plastic foundation/frames for beekeeping, so when I decided to do an expedient Hopkins style queen rearing attempt I needed queen cell cages that I could use to protect cage the queens. These worked well so far. https://enduringtechnologypress.com/2017/07/expedient-queen-rearing-on-plastic-foundation/

https://youtu.be/4sEQIV8cQig