these are cardboard adapter rings are for the JAYO 1.1KG filament spools to help with the AMS system 

these rings have a 194mm outer ring which fit really well to the cardboard spool and the internal plug has a measurement of 54mm 

I have used these for several months now and haven't had a single issue, if you do please post a comment and I will make alterations to the model to suit your needs