Top-TrackĀ® EZ Order Model, nominal 12 ft. system length x 4 ft. width, consists of (1) 7-1/2 ft. track set, (8) 86" posts, (1) 24" tie bar end kit, (12) 74" Top-TrackĀ® mobile posts, (3) 18" mobile kits (stainless steel casters, bumpers, rollers), (12) 18"D x 48"W shelves, (8) 24"D x 48"W shelves, Super Erecta Pro polymer/wire shelving, NSF