3M™ 661X Diamond Lapping Film Disc 3M™ The 3M™ 661X diamond lapping film disc is an ultra-precise abrasive designed for polishing and finishing applications requiring exceptional precision. This disc is made with a polyester film backing, coated with diamond particles, the hardest known material, providing fast and durable cutting performance. The 661X is ideal for fine polishing of hard materials such as ceramics, optical glass, composites, and metals. With the uniform distribution of diamond particles, this disc ensures an extremely smooth and consistent surface, minimizing defects and scratches. It is widely used in the electronics, optics, and industrial manufacturing sectors, where finish quality and precision are critical. Learn more