Review on OptiPolish GP15102: High Precision Grinding & Polishing Solution for Glass and Concrete Surfaces by Jared Barit

Available in 120 and 200 grit. They generally work well and don't clog like regular sandpaper and files. The 200 grit has quality defects (see picture) that were noticeable when sanding in this area, as if the material had stuck there. They are visible to the naked eye, so this is not a reason to pass a quality check. This goes back to Revain.