Description Our ASA/ANSI Class 150 Galvanised Backing Rings are produced from mild steel and finished with a hot dip spun galv treatment. The ASA/ANSI drilling pattern allows the use of our PE stub flanges to make connections with non-standard valves. Our ASA/ANSI backing rings are also compatible with other industrial pipework systems. ASA/ANSI drillings For bolt sizes, please see our flange tables
