Straight Adapter Fitting #3 x 3/8 MPT

The Straight Adapter Fitting #3 x 3/8 MPT from FRAGOLA is an essential fluid transfer component designed for custom fuel systems, cooling loops, and hydraulic applications in high-performance vehicles. As a mechanic working on engine swaps and aftermarket fuel system installations, you'll recognize this fitting as a critical junction point where different line sizes or materials need to connect seamlessly. FRAGOLA's reputation for precision engineering makes this adapter a trusted choice among builders who demand leak-free performance under pressure and thermal cycling.

This straight adapter features a #3 size on one end and a 3/8" male pipe thread (MPT) connection on the other, allowing you to bridge incompatible line standards without routing extra hose or adding unnecessary complexity to your plumbing. The straight configuration—as opposed to angled or tee adapters—ensures minimal turbulence and pressure drop, critical when fuel delivery precision matters at high RPM. Forged aluminum construction provides durability while remaining lightweight, and the compact 1.35" x 1.15" footprint fits tight engine bays where space-conscious builders operate. The 3/8" MPT threads cut to industry standard specifications guarantee hand-tight and wrench-tight sealing without stripping or galling even after multiple disassembly cycles.

This fitting serves racers, street rodders, and engine builders who are transitioning between -3 hose-end and pipe thread systems—common when integrating fuel cells, custom fuel rails, or aftermarket pump outlets into OEM or modified fuel delivery paths. Installation is straightforward: apply thread sealant (PTFE tape or liquid thread locker) to the MPT end, hand-tighten until snug, then use an appropriate wrench to seat the fitting firmly. Verify compatibility with your specific line type and fluid before installation, as FRAGOLA adapters handle gasoline, diesel, coolant, and hydraulic oils in performance-rated applications.