This document discusses the manufacturing process of coils used in industrial and commercial applications. It describes the following key points in 3 sentences: The document reviews the manufacturing process of coils at ZECO Aircon Ltd over one year. It describes the various steps of coil production including aluminum fin generation using an imported fin press machine, hair-pin bending using a Burr-Oak machine, and testing of completed coils by pressurizing them up to 550 psi and checking for leaks. The coils produced are used in various industrial and commercial applications such as air conditioning, refrigeration, and heating systems for buildings, vehicles, and more.