BSF SOCKET ALLEN CUP POINT GRUB SCREWS HT STEEL 1/4" 5/16" 3/8". Thread - BSF. Type - Socket cup point grub screws. Grade - 12.9 High Tensile steel, none plated steel. Thread sizes - 1/4" - 26 tpi, 5/16" - 22tpi & 3/8" - 20 tpi.
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