STANDARD METRIC: Our M6 screws and nuts conform to the standard metric system. SPECIFICATIONS: M6x50mm (20 pieces), M6 nuts (20 pieces). QUALITY AND RELIABLE: Our goal is to provide competitive prices and efficient, high-quality products. Made of 304 stainless steel, this product is not easy to rust, resistant to moisture, oxidation, corrosion, acids, and alkalis, and has high hardness. It is non-polluting, healthy, lead-free, environmentally friendly, and non-toxic. WIDE APPLICATION: Electronic products, mechanical products, digital products, electrical appliances, electromechanical products, means of transportation, airplanes, trams, cars, etc. Warm Tip: The product contains small parts. Do not let children play with them to avoid accidental ingestion.