external hexagon according to DIN 3126 shape E 6,3 (1/4")
PB Swiss Tools - PB E6.400/8 referenced screw product produced by high technology. You can ask all the codes and references except PB E6.400/8 too. It distinguishes with price and quality among the similar products. It produced result of tests of laborotory for years. PB E6.400/8 referenced product is an original piece of your foundation or machine, original parts makes your machine live longer.
