Add on poles allows you to easily add on shelves or create custom sized units (combined with Extra Shelves and Shelf Connecting Hooks). Includes levelers for uneven floors and four 36″ posts, combine two posts for 72″ high shelving. Allows you to easily add on shelves or half-height shelf units. Levelers for uneven floor. Combine two posts for 72″ high shelving. Color: Black; Overall Width: 36″; Material(s): Wire; For Use With: ALE-SW50; SW58.