BSC sizes include - 1/4" x 26 BSC, 5/16" x 26 BSC, 3/8" x 26 BSC, 7/16" x 26 BSC and 1/2" x 26 BSC. Thread repair kits / helicoil kits. WHITWORTH sizes include - 1/8" x 40 BSW, 3/16" x 24 BSW, 1/4" x 20 BSW, 5/16" x 18 BSW, 3/8" x 16 BSW, 7/16" x 14 BSW and 1/2" x 12 BSW.
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