The nozzle is a small but very important component. The nozzle is the last element of the air handling system before the chamber. It moves along the piston head by means of a hanger.

Its job is to guide the ball into the hop up chamber and direct the airflow from the air handler to apply maximum surface area to the ball.
Inside the nozzle we find one or two O rings for sealing. These are most often made of metal, but we can also see cheaper plastic ones.

Is it better to use a plastic or a metal nozzle ?

Generally, metal is better because of its precision manufacturing and thus reducing the possibility of air leakage due to technological error.

They have different lengths for different guns and mechaboxes, so in case of replacement it is best to use the same length as the original nozzle.

Of course it is possible to modify its length, but in this case you will lose the warranty of the product.

NBU nozzles have an enlarged diameter for higher air volumes and are therefore incompatible with standard cylinder heads and other NBU parts