AISI (American Institute of Steel Construction) Stainless Steel Square Rods are considered a universal fitting steel rod which is suitable for use in CNC and other machine tools. Square rods feature an exceptional weldability combined with good tensile strength and corrosion resistance. Square rods are ideal for CNC cutting, drilling, stamping, and engraving. These types of steel rods come in various sizes. The steel square rod size depends on the task. In general, the smaller steel square rod size is used for cutting thicker gauges of sheet steel while the larger square steel rods are used for drilling.