I use this sanding adapter daily for post-processing 3D printed parts and scale models. It fits 25 mm sanding discs cut from standard sandpaper. I use coarse grit (P80–P120) for rough sanding and fine grit (P400–P1000) for finishing. Foam-backed sheets also work well for softer contact. P.S.: I found other designs online, but none met my needs—so I created my own, with better fit, stability, and usability.