I originally printed and used the well constructed spool holder designed by Simone Spezzigu https://www.printables.com/model/597464-improved-spool-holder-for-kingroon-klp1, but needed something wider for a couple of older spools of filament I had laying around, so I designed this wider spool holder. It is in two parts and uses a M3 heat insert (diameter=4mm, height = 5mm like adafruit 4255) to fasten the end knob to the spool holder rod. The spool holder is fastened to the printer using the two screws for the original spool holder. 

In addition to being able to take wide spools it also support spool with a small center hole - if the spool has a very very small hole, the end knob can be removed to place the spool and then remounted afterward :-)