These are 1RU and 2RU vented rack faceplates for standard 19" racks.
The 2 Rack Unit (RU) vented faceplate can be used as a blank plate in a rack or in conjunction with the 2RU Universal Cooler. The faceplate comes in a standard black matte finish. General Specifications Dimensions: L - 19” x H 1.75”(48.3cm x 8.9cm) (1RU) L - 19” x H 3.5” (48.3cm x 4.5cm) (2RU) Construction: Matte Black Powder-Coated Steel