BSP Hexagon Lock Nut / Back Nut T316 (A4) Marine Grade Stainless Steel - Parallel Threads (BSPP / G Thread). (conical male thread, cylindric female thread). o thread angle. Angle of threads 55°. The ISO 7 tapered Whitworth threads are equivalent to DIN 2999, BS 21 (BS EN 10226-1), JIS B0203.
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