Gun Metal Nozzle refers to a type of nozzle made from a specific alloy known as gunmetal. Gunmetal is a type of bronze alloy composed primarily of copper, tin, and a small amount of zinc. This alloy is known for its durability, corrosion resistance, and suitability for various applications. Gun metal nozzles are typically made from a composition of copper (around 85%), tin (around 5-12%), and zinc (around 5-8%).