This tightening knob is made of high quality plastic and iron, with good toughness and impact resistance, strong and durable. Widely used in related industries such as mechanical equipment, electronic equipment, communication equipment, hardware lighting, construction bridges, etc. It can also be installed at the bottom of furniture to improve stability and prevent scratches and noise. Easy to use, just line up the manual tightening knob with the corresponding thread hole and screw it in, no other tools are needed to tighten it. The button head groove design is ergonomic, which makes hand tightening easy. Material: plastic and iron Thread size: M6 x 20 mm Size: M6 x 20 mm Features: This tightening knob is made of high quality plastic and iron, with good toughness and impact resistance, strong and durable. Widely used in related industries such as mechanical equipment, electronic equipment, communication equipment, hardware lighting, construction bridges, etc. It can also be installed at the bottom of furniture to improve stability and prevent scratches and noise. Easy to use, just line up the manual tightening knob with the corresponding thread hole and screw it in, no other tools are needed to tighten it. The button head groove design is ergonomic, which makes hand tightening easy. Features: Material: plastic and iron Color: black. Thread size: M6 x 20 mm Content: 2 tightening knobs with triangular head. Notes: 1. Due to differences in light and monitor settings, the item's color may be slightly different from the photos. Since measurements are taken by hand, the sizes shown may vary from 1 to 3 mm. Thank you for your understanding.