WD simple portable rack series is built with 3 different depth, 450mm, 600mm, and 800mm, and with high-quality steel structure. It is lightweight with casters loaded to provide ultimate mobility for your critical rackmount equipment. These stylish open racks are optimized for small business, research institutions, and professional studio, and are also ideal for countertops or under desk applications. From 4U to 18U, WD series supports any combination of standard rack mount servers or equipment in a compact form factor.