303 gradestainless hex bar in 0.445", 0.525", 0.600", 0.710" and 0.820" these are British standard AF sizes for 1/4, 5/16, 3/8, 7/16 and 1/2 BSF bolts and nuts. 303 grade is a 'free machining' stainless grade, ideal if you have a small lathe and wish to turn your own nuts and bolts.
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