UNF 3/8" Socket Screw Countersunk High Tensile 10.9 DIN7991 UNF 3/8" (24 T.P.I.), Fine Pitch, High Tensile (Grade 10.9), Self Colour. Hex/ Allen Socket Countersunk Screw/ Bolts Countersunk fasteners are designed to fit flush on the connecting surface when fully tightened.
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