Black Anodized Aluminum Adapter, -06 Male JIC 37 deg Flare To 1/8 Inch Male NPT, Straight

You’re on the right track. One side is a -06 male JIC 37 degree flare, and the other side is a 1/8 inch male NPT thread, straight. It’s meant to bridge those two connection types on hydraulic lines.

That's what this one does. The -06 end is a male JIC 37-degree flare, and the other side is male 1/8 inch NPT, all in a straight configuration. Black anodized aluminum keeps it from corroding in typical hydraulic environments, and being an Eaton Aeroquip piece means the machining is tight enough to get a proper seal on both ends without a lot of fuss.

This adapter is constructed from black anodized aluminum, which provides good durability and corrosion resistance, even with a range of hydraulic fluids. For more specific compatibility details, you can consult the fluid compatibility document linked on the product page.