Filament spool box

Hi
I have developed a filament spool case that fits a standard 800g filament roll. The advantage is that the filament cannot jump off the roll when printing or pushing back. This is very important for my planned bowden feeding (will be published here later), because I don't always want to open the filament box. Also attention was paid to minimizing space loss so that 6 colors fit into a small filament box. but more on this later...
( its also published now: https://www.thingiverse.com/thing:28