This 3U vented blank not only keeps your investment cool but it also obscures what lies beneath - be it wires or other unsightly items behind the rack. Proper airflow around equipment is critical to the long-term system performance so you can't be too careful when coming up with your rack's ventilation plan. Convection is the re-circulating of heated air and can result in "super heating" of electronic components -which shortens their life. It is critical to include adequate ventilation to ensure reliability and long life of electronics. Vent panels and spacing are strongly recommended between each heat-generating component in a rack configuration. Use 1U or 2U vents for most components and 3U vents for multi-channel amplifiers including many high current surround receivers. Our lab tests indicate that 33% open area ventilation provides the best airflow while also obscuring the view into the rack. We know you take pride in your rack installations and so do many of your customers. That's why this product features a rich, scratch-resistant powder-coat finish that matches all our racks and accessories.