Spool holders with FF logo.  Accommodates Royella3D filament runout sensor relocator for sale on Etsy. 

All models have a 4mm centered mounting hole.  Heat a 20-30mm length screwn of appropriate diameter and gently pre-thread the models prior to mounting.  Do not overstress with force.  Re-heat the screw as needed to tap the threads.  Let cool to solidify thread profile and then mount as desired.