Large size, easy to assemble. (1) Screw the top 4 bars to the bottom 4 bars. (2) mount the wheels by locking the wheels forward (3) mount the plastic rails on the 4 racks from below (5) place them on the bottom shelf (6) mount the plastic rails to the next desired height (7) slide the next shelf onto the shelves (8) further onto the top shelf . (9) linear shelves if required. Did. Takes about 40 minutes.