Box beam shelf design and double-sided compression clips support loads up to 350 lbs. per shelf (based on a 36"W x 12"D shelf evenly loaded). Shelves can be easily repositioned in one-inch increments. Post Kit includes four 75" high posts (must be ordered with each Shelf Pack). Durable Dark Gray finish. Assembly required. Post Kit includes four 75" high posts (must be ordered with each Shelf Pack).other sizes available.