DIN 16872
DIN 16872 Glass fibre reinforced polyester resin (UP-GRP) flanges for use with thermoplastics pipe fittings - Dimensions
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/1993
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/1993