This version is extended to create clearance when using Spool adapters that center the spool on the Prusa MK4/MK4S injection molded arm. This may work for the MK3 also. I extended it from 117.48mm to 142.06mm. I'm using the cardboard adapter here: https://www.printables.com/model/604366-cardboard-spool-adapter-for-mk4
With the original Prusa Filament guide the spool was rubbing causing friction.
The author remixed this model.
The length is extended from 117.48mm to 142.06mm.