... Silicon Carbide ,imported resin and polishing fiber.Alumina Nylon Grinding Wheel is more sharpper.and easier polishing.cleaning various die ... non-metal substance, such as wood, plastic, glass, stone, etc. pecification:nylon grinding wheels4×1100×255-7P4×1100×259P6×1150×255P6×2150 ... :No blockage under high rotation speed, good brightness, excellent grinding effect, durable for using, convenient to use.