WHITWORTH BSW COUNTERSUNK SCREWS ALLEN SOCKET BOLTS HIGH TENSILE 1/4" 5/16" 3/8"

Whitworth (BSW) Countersunk Screws. BSW (Whitworth) thread pattern. Countersunk socket screws with Allen key drive. High Tensile Grade 10.9. Allen key size: 5/32". High tensile grade 10.9. Allen key size: 3/16".

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