The Orient Star RE-BW0004S00B (also referenced as RE-BW0004S / REBW0004S00B) is a flagship, high-horology Japanese hand-wound mechanical timepiece from Orient Star’s prestigious M45 Collection. Recognized globally by watch enthusiasts and horology collectors by its collection nicknames—the "M45" or "Mechanical Moon Phase"—this 38.8mm dress watch pairs an elegantly finished SUS316L stainless steel case with a sophisticated white dial, a classical sub-dial moon phase display, an in-house manual-winding movement with a silicon escape wheel, an exhibition see-through sapphire caseback, and a premium leather strap. Designed for discerning gentlemen who appreciate traditional high watchmaking, artistic dial aesthetics, and modern mechanical efficiency, it stands as an extraordinary showcase of Japanese craftsmanship. The defining visual highlight of this RE-BW0004S00B reference is its refined white dial layout inspired by the star-filled night sky of the M45 Pleiades cluster. Set beneath a dual spherical sapphire crystal with Super Anti-Reflective (SAR) coating, the dial features elegant Roman numeral hour indices, heat-treated blued steel hands, a fan-shaped 70-hour power reserve indicator positioned at 12 o'clock, and a dual-function moon phase display with integrated date hand at 6 o'clock. The clean white background creates a striking contrast against the dark blue lunar disk and blued hands, ensuring effortless legibility and timeless dress appeal. Beneath its artistic dial, the watch is powered by Orient Star’s flagship in-house Caliber F8B64 manual-winding mechanical movement. Built using Epson's advanced MEMS (Micro-Electro-Mechanical Systems) precision semiconductor manufacturing technology, the movement incorporates a lightweight, friction-reducing silicon escape wheel. This advanced horological innovation increases energy transfer efficiency, allowing the timepiece to deliver an extended 70-hour power reserve while maintaining a daily accuracy rating of +15 to -5 seconds across 22 synthetic jewels running at 21,600 vibrations per hour (3 Hz). The housing features ideal classic dress proportions, measuring 38.8mm in case width (46.5mm lug-to-lug) with a slim profile thickness of 12.3mm and a 20mm lug width, ensuring a comfortable and refined profile under a tailored shirt cuff. Outstanding visual clarity and protection are provided by a dual spherical sapphire crystal treated with Super Anti-Reflective (SAR) coating to eliminate reflection. The reverse side features a screw-down exhibition sapphire caseback that exposes the beautifully decorated movement plates and balance wheel. Engineered for everyday convenience, the case achieves a certified 50-meter (5 bar / 165 ft) water resistance rating. The timepiece comes completed on a genuine leather strap, secured by a solid stainless steel tri-fold deployment clasp with push-button release.
