AN to NPT Adapter - Straight

A tapered thread that never quite seals is the leak you chase all season.

Most fuel and oil leaks trace back to a cheap adapter with sloppy thread tolerances, not the hose itself. The Finish Line Factory AN to NPT Adapter - Straight bridges your NPT port and AN plumbing with a CNC machined 6061 aluminum body, black anodized, in AN sizes from 3AN to 20AN and NPT sizes from 1/8" to 1-1/4". One end threads into the tapered NPT port on your block, pump, or sensor housing, and the other gives you a proper 37 degree male AN flare for your hose end. The fitting you buy once instead of three times.

Benefits

• Threads start square and run smooth, no cross-threading fights at the port
• Wrench flats grip clean, so an aluminum AN wrench seats without slipping or marring
• Hose ends snug down onto the flare with that solid, confident stop
• No slow weep at the NPT joint after heat cycles, no re-torquing every other weekend
• Sizing that matches published AN and NPT specs, so it plays nice with fittings you already own

Features

• CNC machined 6061 aluminum construction, black anodized finish
• Male NPT tapered pipe thread on one end, 1/8" through 1-1/4" NPT
• Male AN thread with 37 degree flare seat on the other, 3AN through 20AN
• Compatible with fuel, oil, water, and air delivery systems
• Lightweight alternative to steel or brass pipe adapters
• Sold as a single fitting in your selected size combination

The Details

The two ends of this adapter seal in completely different ways, and knowing the difference is what keeps your system dry. The NPT side is a tapered thread: it seals by wedging the male and female threads together as you tighten, which means it needs thread sealant (paste or PTFE tape applied carefully, kept off the first thread so nothing migrates into your fuel system). The AN side seals on the 37 degree flare face, metal to metal against your hose end or mating fitting, and it takes no sealant at all. Snug the NPT side into the port first, clock it if orientation matters, then assemble your AN connection with an aluminum wrench so you don't chew up the anodizing. The 6061 aluminum body handles the pressure and heat of automotive fuel, oil, coolant, and air lines while weighing a fraction of a steel pipe fitting. If your port is actually ORB (straight thread with an o-ring boss) rather than NPT, stop and grab the ORB version instead; forcing a tapered thread into a straight-thread port ruins the port.

Kit Includes

• 1x AN to NPT Adapter - Straight (size combination per your selection)

Applications

• AN sizes: 3AN, 4AN, 6AN, 8AN, 10AN, 12AN, 16AN, 20AN
• NPT sizes: 1/8", 1/4", 3/8", 1/2", 3/4", 1", 1-1/4"
• Common uses: fuel pump and regulator ports, oil feed and drain lines, turbo oil supply, coolant lines, catch can plumbing, sensor ports, air and vacuum lines
• Pairs with FLF nylon braided, stainless braided, and push-lock hose via the matching AN hose end