When sourcing a used rolling mill, you must prioritize the mechanical integrity and technical capacity of the unit. Key specs include the mill type (2-Hi, 4-Hi, or 6-Hi), the maximum rolling force (kN), and the roll diameter/face width. It is critical to verify the motor power (kW) and drive system condition, as well as the Automatic Gauge Control (AGC) system's functionality. Ensure the equipment can handle your specific material types, such as carbon steel, stainless steel, or aluminum, and check the maximum input thickness versus the minimum output precision.