Stabilizing items and stopping small objects from slipping through the gaps, these durable plastic wire shelf liners keep everything exactly where you want it on your21"d wire shelving. Select the right size by matching the liner dimensions to the depth and width of your wire shelves. Durable, 1/8" thick PVC construction Rounded corners position around posts Holds up to 300 lbs, evenly distributed Moisture and chemical resistant Liners are cut-to-order and arefinal sale. Please measure shelves and see Product Details section below for exact sizing. To accommodate accessories used on wire shelves, liners must be custom cut. Please note in order special instructions box at checkout if needed.