Everything You Need to Know About Fittings

Fittings are the unsung heroes of any well-built vehicle or vessel. Whether you're routing fuel through a high-performance engine, plumbing a marine bilge system, lubricating chassis components, or connecting brake lines on a race car, the right fitting is what keeps every fluid where it belongs — and out of where it doesn't. A single loose or mismatched fitting can mean the difference between a clean build and a catastrophic leak, making this one of the most critical component categories in any mechanical system.

The world of fittings spans dozens of connection types, thread standards, and materials. Pipe fittings are the backbone of this category, covering threaded connections in NPT, BSP, and other standards used across fuel, coolant, oil, and pneumatic systems in both automotive and marine applications. For race cars, custom builds, and performance upgrades, push-on hose fittings offer a fast, tool-free way to connect braided and rubber hose to AN or NPT ports without the need for crimping tools. Grease fittings — also known as Zerk fittings — are essential maintenance items found on virtually every chassis: ball joints, tie rod ends, U-joints, and steering components all depend on these small but vital parts to accept fresh lubricant. For fuel, brake, and refrigerant lines where a metal-to-metal seal is critical, flare fittings deliver a reliable, pressure-resistant connection. And when one fitting type doesn't quite fit the bill, multi-purpose fittings bridge the gap between different standards, sizes, and thread types.

Key Considerations When Shopping for Fittings

• Thread type and size: AN, NPT, ORB, and metric threads are not interchangeable — always verify the thread specification before ordering.
• Material: Aluminum is lightweight and popular for performance use; brass and stainless steel offer superior corrosion resistance for marine or under-hood applications.
• Pressure and temperature rating: High-boost, high-heat, and high-pressure systems demand fittings rated for those conditions.
• Sealing method: Tapered pipe threads seal on the threads themselves, while AN flare and O-ring fittings seal on a mating surface — mixing methods can cause leaks.

Top Fitting Brands

Vibrant Performance is a Canadian-born performance parts manufacturer with decades of experience supplying both OEM and aftermarket markets. Vibrant's fittings cover AN, ORB, NPT, metric, and imperial styles in a wide array of angles and sizes, making it easy to complete almost any automotive fluid system plumbing project.

Fragola Performance Systems has built a reputation as a leading supplier to the racing world. Fragola's fittings are manufactured from aerospace-quality aluminum machined to mil-spec tolerances, and their signature one-piece hose end design with stainless steel lock wires delivers exceptional strength and leak-free performance.

Snow Performance is best known for its Boost Cooler water-methanol injection systems, and their fittings are purpose-built to support those demanding applications. Snow's ACU-SEAL compression fittings are engineered for guaranteed leak-free operation even when running 100% methanol, using 100% methanol-resistant components throughout.

Groco is a respected name in the marine industry, producing bronze and stainless steel fittings designed to withstand the harsh, corrosive environments found in marine plumbing systems — a trusted choice for through-hull, pipe, and hose connections aboard boats.

Gates is a globally recognized manufacturer of fluid power and power transmission products. Gates fittings are engineered to pair precisely with their hose lines, ensuring reliable sealing in cooling, fuel, and hydraulic applications across a wide range of vehicles.