2018NF E29-200-1*NF EN 1092-1:2018 Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1 : steel flanges
2013NF E29-200-1:2013 Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1: steel flanges