All the Festo fittings have a NPFB designation, and NPFB stands for nickel-plated brass fittings. Fittings have a base metal of cast brass, with an exterior nickel plating. The plating provides corrosion resistance, as well as a high chrome decorative look. If you are using the fitting outdoors, a nickel plating will prevent corrosion by rain and weather over time
Festo pipe fittings are small fittings. Thread sizes range from 1/8 inch to 3/4 inch. A "G" in front of the thread number refers to a British system of measurement, as opposed to metric. Metric sizes are offered as well. Metric thread diameter is up to M5, which is about 1/2 inch. The thread configurations themselves are either NPT, straight or Taper R1/8 to R1. NPT stands for National Pipe Thread, a common pipe thread that has a slight taper. The more the pipe is threaded into place, the tighter the threads squeeze together because of the taper. Straight threads have no taper. Taper R1/8 to R1 is another type of thread taper, referring to how many inches per foot of taper.
The fittings come in various common plumbing shapes, including elbows, T connectors and straight connectors. They also come in Y and X shapes, with the X fittings providing four outlets. It is the responsibility of the system designer to lay out a piping blueprint and to order the fittings from Festo accordingly. The fittings are designed for liquids and gases that do not attack brass. For example, sulfuric acid eats into brass, so these fittings would not be suitable to use with sulfuric acid.
The fittings have a maximum pressure rating of 580 pounds per square inch (PSI). For most applications, this is considerably higher than system designers require. The maximum temperature the fittings can resist is 302 degrees Fahrenheit. For higher temperatures, fittings with a higher temperature resistance are required.