Contents: 1U-10in Cantilever shelf x2, M6 screws x12, M6 plastic washers x12, M6 cage nuts x12 Dimensions: 1.75 in H x 19 in W x 10 in D; Usable Surface Area: 17.5 in W x 10 in D Weight capacity: 55lbs; constructed from 1.5 mm heavy duty cold rolled steel with a durable black electro-static powder coated finish Vented shelf helps to improve air flow and keeps your equipment from overheating EIA/ECA-310 compatible; Fits standard 19 racks and cabinets to hold various network equipment like routers, modems, UPS systems and monitors