Poly-Green is designed with a powder coated green epoxy finish that handles temperature and moisture extremes well.Poly-Green, 4 Tier, Wire Shelving Add-On Unit, 42W x 21D x 74H Reinforced shelves with welded surface ribs for added strength Includes 2 posts with leveling feet, 4 shelves, snap-on sleeves and S-hooks to join units..