Filament spool spindle

When the filament spool has a core hole too small for the spindles on your printer this hooks on to the lip of the case and allows you to use spool with a small diameter hole. I ran into this when I bought some Taulman "Bridge" nylon filament. It is designed to hang on a slight angle to keep the spool on the spindle without requiring any kind of keeper on the end of the spindle. It will hang a Bridge spool above the spindle on the back of the machine without having to remove the machines built i