The AD54-2448P Wire Shelving Add-on Kit is used to expand the size of the Wire Shelving Starter Kit. It shares two posts with the unit. Features: .Can be configured in straight line, back to back and in an L-shape .Supplied with 2 posts, 4 shelves and 8 S-hooks .You can purchase extra shelves separately .Once the Add-on Kit has been fitted the starter kit cannot be made mobile