AD54-2130BK Black epoxy wire shelving 4-shelf add-on kit allows you to expand your starter kit by sharing a set of posts. Configuration options include straight line, back to back and right angles (L-Shape). Add-on kits come complete with 2 posts, 4 wire shelves and s-hooks. Additional shelves may be purchase separately. Please note units with add-on kits cannot be made mobile. Includes 2- 54" posts, 4- 21" x 30" shelves and 8- S-Hooks. Easy to assemble. Finish: Black Epoxy.