I designed this as i didn't get any cardboard re-fill sleeves with the ams that came with 4 spools.

this has been designed in a way the sleeve goes onto the spool first then you slide the filament into the hole there is enough friction that it wont come loose but the ams will pull it free when your at the end of your roll without pulling the spool forward.

I have kept rfid tags from spools and wrote on them the colour and material so i can use them with this sleeve for ease of use
 

I am trying to regularly upload stuff and they have no licence you can print and sell if you like.

happy printing.