HO (Highly Optimised) steel was developed by JDT particularly for the mining chain application. Due to precise alloying with tungsten, JDT has achie-ved significantly higher toughness even by high strength in comparison to standard steel 1.6758 according to DIN 17115. Resistance to stress corrosion cracking was also increased (see Figure). Chains made of HO steel reach significant increase of performance, durability and operational safety. This previously patented HO steel is also used for the lifting chain programme ENORM and is a basis for the real Grade 100 according to DIN EN 818.