Non-woven belts are made of an abrasive impregnated nylon material that is often used for the scratch pattern it leaves. It leaves a very uniform scratch pattern typically used in applications where a satin finish is desired.
Keep in mind these recommendations are guidelines: the actual non-woven material is not officially rated in terms of grit. However, these recommendations match our (and customers experience) of what to expect.
Coarse: 40 to 60 grit
Medium: 80 to 120 grit
Very Fine: 150 to 180 grit
Ultrafine: 220 grit
2" x 48" belts offer the best middle ground between heavy duty grinding and finer detail work blades can require—e.g. sharpening or detailed handle work. This makes the 2" x 48" size one of the most common belt sizes for knife making for profiling, bevel grinding, detailed edge sanding, surface conditioning, and sharpening.
Common machines our customers use for 2" x 48" belts come from manufacturers such as Jet, Rockford, PRM, Kalamazoo, Multitool, and Burr King.