320 Grit Silicon CarbideSandpaper 4-1/2" x 11" Sheet (400 Sheets), 400PK, Klass Tools, Mfr#: KLA-CON-SAN-WSC-P0320-LHx400

Silicon Carbide sandpaper is sharper and more friable, therefore it is still a long-lasting product and is ideal for uses on harder materials, rougher surfaces, and for polishing, due to its hardness and sharpness. It is best for metals (particularly harder metals) and is the only grain that can be used on glass, stone and marble.