4An Bulkhead Nut - Steel 7/16-20

The 4AN Bulkhead Nut - Steel 7/16-20 from FRAGOLA is a precision-engineered fitting component designed for high-pressure fluid systems in automotive, marine, and industrial hydraulic applications. This steel bulkhead nut secures AN-standard hose connections to bulkhead fittings, ensuring leak-free seals in demanding environments where vibration and temperature fluctuations are common. Fabricated to exact AN (Army-Navy) specifications, it is an essential component for anyone building or maintaining custom hydraulic lines, fuel systems, or brake circuits.

Constructed from hardened steel with a zinc oxide finish, the 4AN Bulkhead Nut features a 7/16-20 thread pitch that mates directly with standard 4AN male adapters and bulkhead fitting bodies. The zinc oxide coating provides corrosion resistance while maintaining excellent grip and thread engagement under pressure. At just 0.02 lbs with compact dimensions of 1 x 0.5 x 2 inches, this nut is lightweight yet robust enough to withstand the rigorous demands of high-pressure systems operating at hundreds of PSI. The precision threading and material composition ensure consistent performance across repeated installation and removal cycles without galling or stripping.

This bulkhead nut is ideal for fabricators, mechanics, and enthusiasts building custom hydraulic assemblies, fuel injection systems, or racing fuel cells. It pairs seamlessly with FRAGOLA AN adapters and fittings, providing reliable assembly of bulkhead connections where space is limited or multiple lines converge. Installation is straightforward—simply thread onto the 7/16-20 bulkhead fitting body until snug, taking care not to over-torque. For maximum service life, use with compatible 4AN hose and male AN adapters, and apply thread sealant if the system operates at extreme pressures or temperature variations.