New 3M Micro-Finish Film is a fast cutting abrasive for precise, uniform, close-tolerance finish. High strength polyester film backing and micron-graded aluminum oxide mineral resin is bonded for durability. The particles are electro- statically charged so all particle points are going in the same direction. This process increases the precision of the belt. This material is ideal for; tool and de work, gunsmithing, jewelry making, watch repair and medical devices. This material works well on both metal and plastic