Proto one peice 90-Degree PVC fittings are made out of white .020 PVC and come complete with fiberglass inserts to complete a fiberglass pipe insulation elbow installation. Proto PVC fittings fit multiple sizes of pipe size and insulation thickness combinations. Please review the below fitting size chart to determine the correct fitting size for your application. To use the chart find the pipe size along the side of the chart and move over across the chart to the insulation thickness that is on the pipe. Where the pipe size and insulation thickness meet on the chart will give you the correct fitting number to select. For iron pipe fittings use the blue chart top and for copper fittings use the green chart top. Once you have selected the correct fitting "number" use the drop-down box by the item to select that fitting number and add to your shopping cart.