This is a rigid mount adaptor for the Dragon hotend with a magnetically held hotend cover. The hotend cover is designed to re-use the existing Ender 3 V2 fans and the adaptor plate is compatible with the Creality BL-Touch ABL kit.
The magnets used are round 6mm x 3mm. A small drop of CA glue is all that is required to install them into the print. Be careful of magnetic pole orientation when installing the magnets.
You do loose a few mm of Y travel due to the thickness of the adaptor plate moving the hotend forward on the machine relative to the stock hotend position.
The author hasn't provided the model origin yet.