DIN 4925-2
DIN 4925-2 Well screens and casings of unplasticized polyvinylchloride (PVC-U) for tube wells - Part 2: DN 100 to DN 200 with trapezoidal thread
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/2017
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/2017