DIN 5683-1
DIN 5683-1 Round steel link chains - Buoy chains for mooring of buoys - Part 1: Round steel link chains, grade 4
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 01/01/2008
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 01/01/2008