Anderson Metals Brass Tube Fitting, Reducing Union, 1/4" x 3/8" Flare Reducing union to connect two tubes of different diameters Flared tube connections on both ends Brass for corrosion resistance, ductility at high temperatures, and low magnetic permeability Operating temperature range of -65 to +250 degrees F Resists mechanical pullout for a more secure connection These fittings contain lead and are not allowed by federal law to be installed for potable water use in the U.S.A. and its territories.