Filament guide for Ender 3 V2. This model was designed to be used with the mount for the Creality runout sensor. I do not use my runout sensor, so I designed a filament guide mount that uses the 4 holes for the filament runout sensor. See attached pictures of the runout sensor mount (circled in blue). 

The roller wheel is designed to use a 13 mm OD bearing, with a 4mm ID. 

The 4 holes on the mount are for 3mm screws. If you have this filament runout sensor it should have came with the screws.