This high quality solid brass spigot is double-sided. It has as a common 1/4-20" male thread on one side and a common 3/8" male thread on the other. It is excellent for joining various items together. It is the same double spigot included wit all ProMaster 5500 Studio Clamps. This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects and/or other reproductive harm.