Imperial 1604

3/16CC X 1/8NPT 90 DEGREE ORIFICE PILOT

American National Standard Pipe Thread standards, often called National Pipe Thread ("NPT") standards for short, are U.S. national technical standards for screw threads used on threaded pipes and pipe fittings. They include both tapered and straight thread series for various purposes including rigidity, pressure-tight sealing, or both. The various types are each named with a symbol and a full name; examples of the symbols include NPT, NPS, NPTF, NPSC, and others.

An orifice is any opening, mouth, hole or vent, as in a pipe, tube or a plate used to either regulate or measure the intake or output of a gas or liquid, e.g. "air orifice", or "orifice plate".

A pilot light is a small gas flame, usually natural gas or liquefied petroleum gas, which serves as an ignition source for a more powerful gas burner. In a pilot assembly, there is thermocouple sitting in the pilot light's flame. The electricity that is created from the flame contacting the thermocouple wire runs to a small electromagnetic valve and holds it open. If the pilot light blows out, the thermocouple quickly cools off. It stops generating electricity and the valve closes.