RockRidge paper sanding discs are made with tear-resistant backing and open coat aluminum oxide grains along with a load-preventing stearate.
For our discs with grits ranging from 4-120, they are made with a sturdy, d-weight paper for light stock removal and surface preparation.
For the 150-800 grits, we use a more flexible, c-weight, latex backing for finishing and blending.
50 hook-and-loop discs per box for the 40 grit discs. 100 discs per box for 80-800 grit discs.