Thread size: M5 x 0.8mm. Size: (overall) 16x10mm / 0.63"x0.39"; thickness(knurled part): 5mm / 0.2". Material: Made of good quality metal, zinc plated finished, rustproof and durable to use. Advantage: This facilitates tightening by hand, commonly used in electronics applications. Common on 3d printer beds, machine tools, cabinets, tool boxes, and great for maker projects and things that need adjusted quickly. Works with M3 bolts, studs and screws with a 0.5mm pitch. Quantity: 100 pieces Note: It does not include other things, the color is based on the first picture, and the other pictures only show the effect Due to the differences between different monitors, the picture may not reflect the actual color of the item. Due to manual measurement. Please allow deviation. Thanks!