Husqvarna 542 20 40-63  Nozzle

The purpose of the Nozzle is to control the direction and characteristics of a fluid flow as it exits or enters an enclosed chamber or pipe. The nozzle can be particularly important in something like a carburetor nozzle (fuel jet), where the jet controls the amount of fuel entering the engine. Nozzles can fail from contamination, poor filtration, improper lubrication, and incorrect installation, and can lead to a decline in engine and other equipment performance.