Diamond resin sanding belts are a great choice for sanding and pre-polishing stones and glass. These are designed for light grinding and pre-polishing, not for shaping or removing a lot of material. These high quality discs last longer than traditional silicon carbide discs because the diamond doesn't break down during use making it effective for longer. These discs do NOT have PSA backing. If you are looking for our diamond discs with magnetic backing - click here.