Earl's 981666 Blue Anodized Aluminum -6AN Male to 3/8" NPT Straight Adapter AN adapter side seals on the flare (cone) not the threads and the NPT side seals on the threads Precision machined to exacting tolerances for trouble-free performance Made in the USA Should not be overtorqued to prevent damage to part Use Teflon tape or sealing compound during assembly for proper sealing