HOSCO FRET POLISHING RUBBER 400 GRIT
Easy and fast fret polishing tool. Erasing the small scratches of the fret or polishing dirty frets. Due to their softness rubber fits fret arch and radius perfectly. Also it doesn't damage the fretboards. Available to buy individaully or a set of 3. 180, 400 and 1000 grit.
This one is 400 grit.