A straight adapter carrying a 37-degree AN male flare at one end and a BSP parallel male thread at the other, used to run AN hose onto BSP-tapped components. BSP uses a 55-degree Whitworth thread form, which is fundamentally different to the 60-degree NPT form, so the two standards must never be substituted for one another. Because the BSP thread here is parallel rather than tapered, it seals at the shoulder on a bonded washer or O-ring and gains nothing from thread sealant. The AN side seals metal-to-metal on its flare face. Check the exact port thread on your component before ordering, as this listing does not publish size figures.