Is collapsible and perfect for showrooms, warehouses or anywhere with tight spaces. Knocked-down construction - Z base comes in 4 parts that bolt together. Hangrail & Uprights are made of 1¼" round tubing. The hangrail comes in 2 parts and measures 60½" long. 4" industrial casters with lower shipping costs vs RZK/7 which has welded Z-base, not bolted.