5 pack - 3" x 21" Economy Aluminum Oxide Belts (Best for: Wood)Best for wood sanding Can also be used as a cheaper option for general metal sanding X weight poly cotton blend backing Dry applications Choosing a Grit Coarse Grits (24 80): For heavy material removal, weld grinding, or shaping. Medium Grits (100 180): For blending, deburring, and intermediate smoothing. Fine Grits (240 400): For finishing or preparing for polishing. Super Fine (800 1200): For mirror polishing or fine detailing. Choosing a Backing

Choosing a Backing Weight

·         Fine Grits (240-400): For finishing or preparing for polishing

o   Final polishing before coating or plating

plastics & composites

· J-weight poly/cotton blend backing

·         Best for non-ferrous metals like: aluminum

· Best for curved/contoured applications on a variety of metals

·         Can be used on other materials when needing something more aggressive

·         Standard Ceramic material is best used on hard metals

o   Removing deep scratches

· Dry applications

·         Y-weight polyester backing