The flexo or flexographic printing press is used commonly in the food packaging industry. The flexo or flexographic press is commonly associated with the plastic industry as many of the food packaging products use plastics. Besides the food packaging industry, the flexo printing press is also associated with industries including paper bags, carton and cardboard box, medical packaging, sanitary product labels, and the diaper industry. In recent years the flexo printing press is also found in the process for printed electronics manufacturing such as RFID, OLED lighting, functional substrates, circuit boards, and sensors. The Flexo press can print on various substrates or materials. This includes porous substrates such as paper, carton and cardboard. For non-porous substrates family including PE, PET, PP, and aluminum. The substrate is fed into the flexo press in a roll form from the unwinder unit. The tension of the substrate needs to be controlled with precision as it moves through the printing and drying units. The capability to main a precise substrate tension makes all the difference in print quality. This is a crucial disguising point for great flexo press and mediocre flexo press. Any tool will have its advantage and disadvantage and flexo press is no different.