This nickname ( ultimate steel king) refers to the Patek Philippe 5712/1A-001, the stainless steel Nautilus with the asymmetric dial (power reserve, moon phase, date, small seconds). Among steel Nautilus references, the 5712A is often considered more interesting than the time‑only 5711A because of its extra complications. “Ultimate steel king” suggests that for many collectors, the 5712A represents the pinnacle of steel sports watches – it combines the iconic Genta design with useful functions and a luxurious yet understated wrist presence. A top‑tier custom 5712A would include a precision CNC case, a high‑quality aftermarket dial/hands/moon phase, and a non‑indexed 240 movement with a 22K gold rotor.