M8 female thread knurled knob are made of high quality plastic, with good toughness and strong anti-aging ability and long service life. The star-shaped design is used to increase the sense of use when rotating. The surface of internal M8 threaded knob is polished, so it won’t hurt your hands even if you rotate it for a long time period. Female thread diameter: M8 , head diameter: 32 mm . There are 20 M8 clamping knobs in the package, two sizes, to meet your different needs. Handle nuts are widely used in machine tools, mechanical equipment, instrumentation, food and pharmaceutical industrial equipment.