The Series 5405 Straight Male NPT x Female NPT hydraulic adapters, made from durable carbon steel, are essential fittings designed to provide secure connections for fluid and gas transfer in hydraulic systems. Utilizing the National Pipe Taper (NPT) standard, these adapters feature tapered threads that create a reliable seal through thread deformation, ensuring a strong metal-to-metal connection when tightened. The nominal pipe size can be determined by measuring the thread diameter and subtracting 1/4". NPT connections have been widely used in the U.S. for over 100 years, making them a trusted choice in various applications. However, they are ideal for single assembly applications and not recommended for frequent disassembly, as this can lead to wear on the threads. These adapters are perfect for professionals seeking dependable and efficient hydraulic solutions, ensuring optimal performance in fluid transfer systems.