4RU Blank Filler Panel The Blank Panel is a practical and versatile, steel, blank panel featuring a flat face. Use blank panels to cover unsightly open space in your rack, or to protect your equipment from dust and other foreign debris. This model features a durable, black, powder-coat finish. Features: - 4 Rack Space - Solid, steel construction ensures a lifetime of use. - Use a blank panel to fill unsightly open space in your rack, or to protect your equipment from dust and foreign debris.