Selkirk 105230 Round Type B Gas Vent Adjustable Elbow, 90-Degree, 5", #5RV-90The RV line of Selkirk round vent pipe and fittings is designed for use on approved gas appliances in residential and light commercial and industrial applications. Round vents for large appliances will be found in the QC section which follows. Size 5" Part No. 5RV 90 Measures: 6 38" x 4 1116" Used when an offset is required to avoid obstructions such as rafters, joists and other construction obstacles Used to orient pipe between vertical and