Brennan PCDT2700-04-04-B Nickel-Plated Brass Push-to-Connect Tube Fitting, Bulkhead Union, 1/4" Tube OD Bulkhead union fitting to allow tube connection on either side of barrier Accepts nylon and polyurethane tube fittings Made of nickel-plated brass for durability and corrosion resistance Working pressure of up to 290 psi Operating temperature ranges from -4 to 175 degrees F