Flat countersunk screw is suitable for power, aerospace, office equipment, petrochemical, electronics, communications, shipbuilding industry, machinery, etc. You can also see them in construction, manufacturing, engineering, assembling, landlord, repairmen, and other DIY projects.SpecificationDrive Type: Hex SocketMaterial: Carbon SteelUnified Thread Specification: 3/8"-16 UNCInner Hex Dia: 5.5 mm / 0.22 inchHead Outside Diameter: 18.83 mm / 0.74 inchTotal Length: 1-1/2 inchHex Spanner Head Dia: 7/32（5.5mm)Strength Level: 10.9 GradePacking List: 10 Pcs x Flat Head Socket Cap Screws with 1 Pcs x Hex SpannerAdvantage1. Hex drive machine screws are made of carbon steel with a corrosion-resistant black oxide finish, durable, and wear-resistant， providing good strength and corrosion resistance in bad environments.2.
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