<br>The bulkhead fitting has 1/4" National Pipe Taper female ends.<br/><br>A washer and nut create an air-tight seal with the bulkhead.<br/><br>The fitting is made of brass for corrosion resistance, ductility at high temperatures, and low magnetic permeability. It has a working pressure of up to 1,200 pounds per square inch (psi).<br/>