When evaluating a cardboard box shredder, you must prioritize the cutting capacity (width and thickness) and the motor power (kW). For heavy-duty recycling, look for machines that can process multi-layer corrugated cardboard with a feeding width of at least 325mm to 430mm. Ensure the motor is rated for continuous operation (S1 duty cycle) to prevent overheating during high-volume shifts. Additionally, check the output type: some machines produce cushioning mats (net-like) for packaging filler, while others produce strips or chips for volume reduction.