UNF 1/4" Socket Cap Screw High Tensile 12.9 Self Colour DIN912 UNF 1/4" (28 T.P.I.), Fine Pitch, High Tensile (12.9), Self Colour DIN 912. A screw is fully threaded and a bolt is partialy threaded. ‘Socket,’ refers to the hexagon shaped indentation found on the top of the fasteners’ head.
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