Thread & Fit: UNC coarse 1/2"-13 thread,External Hex drive. Compatible with standard 1/2"-13 bolts, screws, and studs. 1/2"-13 UNC (Coarse) 3/4" (0.750") 0.866" (approx.). 7/16" (0.438") Plain / Uncoated Stainless.
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