These polyester-cotton heavy X-wt backed AO belts are a good tool for sanding of both metal and wood. They are suitable for both ferrous and non-ferrous metal. It's also suitable for sanding both hardwood and softwood.
 
 
Belt backing is X-wt polyester-cotton blend
Sold In Packs of 5 and 10 belts
Available in grit P36, 40, 50, 60, 80, 120, 220, 320, 400