Stainless steel duplex stainless steels are achieved with an overall lower alloy content than similar-performing super-austenitic grades, making their use cost-effective for many applications. Duplex grades are characterized into groups based on their alloy content and corrosion resistance. Precipitation hardening stainless steels have corrosion resistance comparable to austenitic varieties, but can be precipitation hardened to even higher strengths than the other martensitic grades. The most common, 17-4PH, uses about 17% chromium and 4% nickel. The designation "CRES" is used in various industries to refer to corrosion-resistant steel. Most mentions of CRES refer to stainless steel, although the correspondence is not absolute, because
The Stainless Steel Rat name is not revealed to the reader. The Kekkonshiki, also known as "The Gray Men", are a human culture who initially prefer domination to coexistence. Their expertise lies in using technology to manipulate sentient minds, and they have manipulated both humans and aliens on a grand scale. Jim has experienced one of their techniques (in which a gray man agent seemingly severs his hands with an axe; this was an illusion). Jim has knowingly opposed them on two separate occasions ("The Stainless Steel Rat's Revenge" & "The Stainless Steel Rat Wants You") however during conversation it is revealed by Kome