OptiGrit PSA Roll Sandpaper - 320 Grit Aluminum Oxide 2-3/4" x 10 yardsOptiGrit 2 3 4" x 10 Yards Aluminum Oxide PSA Sandpaper Roll 514D 514C The OptiGrit P320 Aluminum Oxide Sandpaper Roll is perfect for sanding primer coats before applying AP 7541 as a no sand sealer. This medium fine grit removes minor imperfections and smooths primer without cutting too aggressively. Most painters like to spray no sand sealer over either P320 or P400 depending on which primer is being used (check the product's TDS). Get a smooth,