Our Series 6900-O Straight Male ORB x Female NPSM Swivel hydraulic adapters, made from carbon steel, combine ORB and NPSM thread types for secure, leak-resistant connections in hydraulic systems. The ORB (SAE Straight Thread O-ring Boss) side features a straight UNF thread with an O-ring that creates a leak-tight seal when compressed into a chamfered surface on the female port. NPSM (National Pipe Straight Mechanical) connections, on the other hand, use a straight, non-tapered thread with a 30° inverted seat on the female component. The seal is formed when the male component's 30° chamfer compresses against the female seat, creating a mechanical connection. While NPSM and NPTF threads are similar in design, NPTF provides a dry seal without the need for sealant, whereas NPSM requires compression for a secure seal. Both connection types are commonly used in fluid power systems, offering versatility and reliable performance. Care should be taken when selecting the correct thread type to ensure compatibility and prevent leaks.