PENCO Record Storage Racks archive years of valuable records. Quickly assembled dual rivet-type beam connections result in a rigid, boltless connection between beams and posts for wobble-free stability. Combine starters and add-on units to form economical row storage systems. Add-on units utilize a common T-post between units to save time during assembly. Begin rows with two posts from starter and join any number of add-ons to complete the row. Finish with remaining two posts from starter unit. Shelves adjust in 1-1/2" increments. Units come complete with 5/8" particleboard decking or order separately below. Made in USA.NOTE: Shelving units with 670- and 1150-lb. capacities include center supports.NOTE: Box design may vary.