This is a scale case for a 5kg scale Module and the HX711 pcb.

It can be connected to a RaspberryPI and used by the Octoprint Plugin “Filament Scale Enhanced” (https://plugins.octoprint.org/plugins/filament_scale/)

The filament spool holder can be set on top. Like this one from Copanko:

Spool holder for Prusa MINI Flexible

Wiring should be like this:

Raspi                       HX711           Scale Modul VCC 5V               ----- VCC  |  A+ ----- green GND                  ----- GND  |  A- ----- white SCK (Clock) GPIO20   ----- SCK  |  E- ----- black (GND) DO  (Data)  GPIO21   ----- CO   |  E+ ----- red   (VCC)

Scale modul and HX711 can be found on e.g. Amazon or cheeper on AliExpress

You also need 4 M4x16 screws to mount the scale module. You can use 2mm thick foam rubber (4x 14x16x2mm) as soft feets.