BSPT to AN Adapter - Straight

BSPT looks exactly like NPT right up until it leaks.

Japanese and European components frequently carry BSPT ports that look deceptively like NPT and will not seal against it; CNC machined 6061 aluminum, anodized black. The Finish Line Factory BSPT to AN Adapter - Straight carries a male BSPT tapered thread on one side and a male 37 degree AN flare on the other, in AN sizes 3AN, 4AN, 6AN, 8AN, 10AN, 12AN with port sizes 1/8x28 BSPT, 1/4x19 BSPT, 3/8x19 BSPT, 1/2x14 BSPT, 3/4x14 BSPT, 1x11 BSPT. 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: male BSPT tapered thread, sizes 1/8x28 BSPT, 1/4x19 BSPT, 3/8x19 BSPT, 1/2x14 BSPT, 3/4x14 BSPT, 1x11 BSPT
• AN side: male 37 degree flare, 3AN, 4AN, 6AN, 8AN, 10AN, 12AN
• Seals via the tapered BSPT thread with sealant, exactly like NPT practice but on British pitch
• 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 the tapered BSPT thread with sealant, exactly like NPT practice but on British pitch, while the AN side stays a dry metal-to-metal flare, no sealant ever. BSPT and NPT are NOT interchangeable despite near-identical appearance; thread angle and pitch differ. This is the number one confusion to warn on. 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 BSPT to AN Adapter - Straight (size per your selection)

Applications

• Port sizes: 1/8x28 BSPT, 1/4x19 BSPT, 3/8x19 BSPT, 1/2x14 BSPT, 3/4x14 BSPT, 1x11 BSPT; AN sizes: 3AN, 4AN, 6AN, 8AN, 10AN, 12AN
• 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