Straight Adapter Fitting #3 x 1/8 MPT Black

The Straight Adapter Fitting #3 x 1/8 MPT in Black from Fragola is a precision hose connector designed for fuel system, coolant, and fluid transfer applications in custom automotive builds and engine modifications. This adapter serves as a critical interface component when plumbing multiple fuel or cooling circuits together, allowing you to transition between different hose sizes or port configurations without compromising flow integrity. Whether you're upgrading to a larger fuel system for a turbocharged engine, installing dual fuel pumps, or reconfiguring your cooling lines during a comprehensive engine swap, this straight adapter ensures reliable, leak-free connections under pressure and temperature cycling.

Constructed with a black-anodized aluminum or steel body, the Straight Adapter Fitting #3 x 1/8 MPT features a straight-through geometry that minimizes turbulence and pressure drop during fluid circulation—critical when you're running higher fuel flow rates or aggressive cooling demands. The #3 size corresponds to standard hose barb or port specifications common in aftermarket fuel rails and distribution blocks, while the 1/8 MPT (male pipe thread) end accepts standard NPT-threaded ports found on fuel pressure regulators, Schraeder valves, and block-mounted adapters. Fragola's engineering ensures tight tolerances and corrosion resistance, so you can trust this fitting through multiple seasons of track use, street driving, or forced-induction applications where vibration and thermal stress are constant.

This adapter is ideal for mechanics and enthusiasts building fuel-injected swap platforms, supercharged or turbocharged engines, or any custom system requiring modular plumbing architecture. The compact 1.35 × 0.85 × 4-inch profile fits tight engine bays and complex fuel cell installations without adding bulk, and the straight configuration allows for direct, unobstructed flow paths that reduce heat soak in sensitive fuel systems. Install using quality thread sealant (Teflon tape or PTFE-based compound) on the MPT end to guarantee a permanent, vibration-proof seal that won't weep under sustained pressure or repeated thermal cycling.