5/32in (4mm) Union Strai ght One-Touch Fitting

The 5/32in (4mm) Union Straight One-Touch Fitting from VIBRANT PERFORMANCE is a compact pneumatic coupling engineered for high-flow vacuum and boost applications in engine modifications. This one-touch design eliminates the need for traditional threaded connections, making it ideal for builders installing complex intake manifold systems, turbocharger plumbing, and intercooler circuits where quick, leak-free assembly matters. Whether you're upgrading a naturally aspirated engine or fine-tuning a forced-induction setup, this fitting streamlines both installation and future maintenance without sacrificing reliability.

The straight union configuration delivers direct, unobstructed flow through a 5/32-inch (4mm) bore, minimizing turbulence and pressure drop across vacuum lines and light positive-pressure circuits. VIBRANT PERFORMANCE's one-touch mechanism uses a spring-loaded collet that grips the tubing securely without clamps or hose barbs, reducing the risk of separation under boost and vibration. The compact profile—weighing just 0.02 lbs—allows tight routing through engine bays with limited space, while the precision-machined body ensures durability through thousands of heat cycles and repeated connect-disconnect cycles common in development and racing environments.

This fitting is ideal for DIY tuners, professional engine builders, and race teams working with fuel injection systems, vacuum distribution blocks, and boost-control solenoids. The 4mm size pairs seamlessly with standard silicone and polyurethane tubing used in modern swap projects and OEM-replacement hose kits. Installation requires no tools—simply push the tubing into the fitting until it seats fully—and removal is just as fast by depressing the collet collar. Always verify tubing outer diameter matches the 5/32-inch specification to ensure a proper seal on your first try.