Quick Ship - SmartWall Shelf Support, single, for 21" deep shelf, Metroseal 3™ epoxy-coated corrosion-resistant finish with Microban® antimicrobial protection, actual dimensions (DxWxH 23-9/16" x 1-1/2" x 8-3/16"); compatible with Super Erecta® wire & solid shelves, MetroMax® Q; (2) required per shelf