Add or replace the middle shelf in your Avantco UBB2472 and UBB2472G back bar units with the Avantco 178SHLFUBB72 20 1/2" x 18 1/8" middle shelf! This plastic coated shelf quickly swaps out with the one that came in the middle section of your refrigerator so that you can keep using it throughout the day. Shelf clips sold separately.