CLASSIC CAR BOLT KIT - UNF THREAD HEXAGON SETS. UNF hexagon head set screws. UNF thread pattern; 1/4UNF x 28 tpi, 5/16UNF x 24 tpi, 3/8UNF x 24tpi. A2 Stainless Steel Hexagon. Hexagon Head Fully Threaded.
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