Metric M3 screws,Thread Diameter: 3mm; Thread Length:55mm; Pitch Size: 0.5mm. Metric M4 screws,Thread Diameter: 4mm; Thread Length:8mm; Pitch Size: 0.7mm. Metric M5 screws,Thread Diameter: 5mm; Thread Length:25mm; Pitch Size: 0.8mm. Metric M6 screws,Thread Diameter: 6mm; Thread Length:18mm; Pitch Size: 1.0mm. Made Of 12.9 Grade Alloy Steel, Sturdy And Durable, corrosion resistance property, features good wear resistance, high hardness and high strength, can be used in extreme environments. Perfect For Interior Renovation, Mechanical Installation Communication Equipments and Ship Assembly 100% customer satisfaction, if you are not satisfied with the product, you can always send us an email to us, provide you with satisfactory service in the first time, you can also get a full refund, please rest assured to buy. The material is made of high quality 12.9 grade alloy steel. Their surfaces are treated with black oxide, which has excellent corrosion resistance, firmness, wear resistance and low temperature resistance. Widely used in various precision machinery industries, classified instruments, meters, electronic products, household appliances, communication products, automobiles, locks, lamps, toys and so on. Specification: Thread Diameter 3 mm / 4 mm / 5 mm / 6 mm Screw Length ：4 mm - 100 mm High Quality Material 12.9 Grade Alloy Steel Package Included: Socket Head Cap Bolts/Screws For more detailed dimensioning instructions, please see our dimensioning drawings. Warranty: Whenever you need us, please contact us by email or Q&A. We will provide you with professional services and reply to you as soon as possible. If you are not satisfied with the product, you can get a full refund, and you can buy it with confidence.