Size: The Dimention Of 4U DVR rack Length x Width x Height : 45cm x 55cm x 25.5cm. Before Order, it compare this size with your DVR/NVR etc and be sure that this rack is the perfect size for your device. Material: This 4U DVR rack is made from a dominant quality, high gauge sheet metal(iron) and powder coating process. The material we use for this rack is rustproof and Long lasting. Use: You Can apply this 4U DVR rack for your CCTV DVR/NVR/WIFI Routers and other equipments to keep it safe, dust free and neat.