Hex bushing for connecting two pipes with same diameters Male NPT threads on both end for connecting pipes with same ends Brass for corrosion resistance, ductility at high temperatures, and low magnetic permeability Use in plumbing connections, compressed air, hydraulic, gas and other applications, hex nut for easy tightening and loosening 1/4" NPT Male is measure Nominal Outside Diameter Pipe OD(inches) 0.54 inches.