The Series 6404-SS Straight Female ORB x Male NPT hydraulic adapters, made from high-quality stainless steel, are essential components designed for creating secure and leak-proof connections in hydraulic systems. Featuring a female ORB (SAE Straight Thread O-ring Boss) end, these adapters utilize a straight UNF thread and an O-ring to prevent leaks, making them ideal for medium and high-pressure applications as recommended by the National Fire Protection Association (N.F.P.A.). The female port is designed with a smooth, flat machined surface and a chamfer that accommodates the O-ring, ensuring a reliable seal when mated with the male NPT (National Pipe Taper) connection on the other end. NPT connections employ tapered threads that form a metal-to-metal seal through thread deformation, effectively sealing pipes for fluid and gas transfer. The nominal pipe size for NPT connections can be determined by measuring the thread diameter and subtracting 1/4". These adapters provide professionals with a dependable solution for efficient hydraulic connections, combining the benefits of both ORB and NPT designs in one robust component.