Eaton Weatherhead 105X3 Steel Inverted Flare Brass Fitting, Nut, 3/16" Tube OD (Pack of 50) Inverted flare tube fitting nut for use with flare tube fittings in hydraulic fluid transfer applications Suitable for use with 3/16" OD tubes Steel for strength and durability Meets SAE 040110 specifications for tube fittings