BÖHLER P504 is a wrought nitrogen strengthened 21chromium—10nickel—3manganese—2.5molybdenum stainless steel for surgical implants. It is a highly corrosion resistant non-magnetisable stainless austenitic steel – nitrogen alloyed – resistant to intergranular corrosion. Compared to standard Cr-Ni-Mo steel, it offers increased strength and thus also better fatigue properties. The steel is produced as remelt grade and thus fulfils the usual requirements for steel purity as specified for implant material.