AN to NPS Fittings

NPS: the straight-thread cousin that ruins the day of anyone expecting NPT.

NPS ports appear on select senders and OEM hardware, parallel where NPT is tapered. The Finish Line Factory AN to NPS Fittings carries a NPS straight pipe thread on one side and a male 37 degree AN flare on the other, in AN sizes 6AN with port sizes 1/4 NPS. Ideal for fuel, oil, water, and air delivery, and for keeping the whole downstream system in one connection standard.

Benefits

• The odd port joins the AN system instead of dictating its own island of plumbing
• Sealing happens the way this thread standard actually works, not the way NPT habits assume
• Downstream, everything is familiar flares and familiar wrenches
• One correct adapter replaces a drawer of near-miss attempts

Features

• Port side: NPS straight pipe thread, sizes 1/4 NPS
• AN side: male 37 degree flare, 6AN
• Seals via a washer or sealant at the parallel NPS joint, since straight pipe threads do not self-seal
• Suits fuel, oil, water, and air delivery
• Sold as a single fitting

The Details

Thread standards differ in exactly one place that matters: where the seal lives. Here it lives at a washer or sealant at the parallel NPS joint, since straight pipe threads do not self-seal, while the AN side stays a dry metal-to-metal flare, no sealant ever. FLF's site copy for this listing is mismatched (describes a hose separator), so all copy here is held to the title, sizes, and general NPS practice only. Assemble the port side first, confirm it holds, then bring the AN plumbing to it with the body backed up by an aluminum wrench. When a port's identity is uncertain, measure before ordering: thread pitch gauges and calipers cost less than a stripped component, and the difference between tapered and parallel is visible in profile.

Kit Includes

• 1x AN to NPS Fittings (size per your selection)

Applications

• Port sizes: 1/4 NPS; AN sizes: 6AN
• Common uses: adapting OEM and specialty ports to AN plumbing on fuel, oil, coolant, and air systems
• Mates to female AN hose ends in the matching size downstream