{"product_id":"citizen-collection-open-heart-nh9150-52e-mens-watch","title":"Citizen Collection Open Heart NH9150-52E Men's Watch","description":"\u003cp data-path-to-node=\"6\"\u003eThe Citizen NH9150-52E (cataloged within the prestigious Citizen Collection \/ Mechanical Open Heart Series) is an authoritative, high-performance Japanese automatic mechanical sport-dress timepiece. Engineered for discerning horological enthusiasts who appreciate the living, exposed heartbeat of mechanical watchmaking paired with modern athletic wrist presence, this reference delivers a commanding, high-contrast aesthetic in an all-stainless-steel construction. Across international watch forums, Japanese Domestic Market (JDM) collector circles, and everyday carry (EDC) communities, it has earned defining community nicknames—the \"Open Heart\", \"Black Open Heart\", \"Steel Open Heart\", \"Sporty Open Heart\", \"Obsidian Open Heart\", or \"Mechanical Heart 41\"—for its prominent open-heart balance wheel aperture at 9 o'clock, rich sunray black dial plate, monochromatic brushed and polished stainless steel architecture, exhibition display caseback, and robust 100-meter water resistance rating. It unites a sculpted 316L solid stainless steel case in a versatile 41.0mm diameter with an evocative black dial, faceted applied silver-tone indices, an in-house Japanese automatic mechanical caliber, durable crystal glass, and an integrated solid stainless steel construction. Perfectly calibrated for corporate executives, creative leaders, and mechanical watch collectors seeking a bold, mechanically expressive daily timepiece that transitions effortlessly from formal boardroom meetings and tailored suits to celebratory dinners and active weekend travel. The defining visual centerpiece of this NH9150-52E reference is its captivating open-heart dial architecture. Anchored at the 9 o'clock position is a circular skeletonized window framed in polished silver, offering an intimate, uninterrupted view of the beating balance wheel, hairspring, and pallet fork in continuous mechanical motion. Finished in an ultra-fine sunburst radial brushing, the deep black dial plate catches ambient light across dynamic smoky gradients, providing an intense, high-contrast stage for the exposed escapement. Circling the outer perimeter is a stepped chapter ring marked with crisp white minute demarcations for down-to-the-second precision. Prominent three-dimensional, applied silver-tone faceted baton hour indices line the hour positions, diamond-cut and treated with high-performance luminescent compound to ensure effortless readability in low-light environments. Broad silver-tone sword-style hour and minute hands sweep authoritatively across the dial alongside a needle-thin central sweep seconds hand. Framing the dial is a fixed solid stainless steel bezel with a slightly thickened profile and mirror-polished angled chamfer that accentuates the case’s athletic shoulders and downward-sloping lugs. Beneath its tailored exterior, the watch is driven by Citizen’s in-house Calibre 8229 Japanese automatic mechanical movement, engineered and manufactured at Citizen’s dedicated horological facilities in Japan. Beating at a steady frequency of 21,600 vibrations per hour (3 Hz), this 21-jewel self-winding caliber harnesses the natural kinetic motion of the wearer’s wrist to wind the mainspring, delivering approximately 40 to 42 hours of autonomous power reserve on a full wind. In addition to automatic rotor winding, the Calibre 8229 features convenient manual hand-winding capability through the crown, allowing the wearer to wind the movement smoothly after periods of rest. The caliber is equipped with a hacking seconds (stop-seconds) mechanism that halts the seconds hand when the crown is pulled out, enabling down-to-the-second time synchronization. Built with Citizen’s proven shock-resistant balance architecture and Japanese Industrial Standard (JIS) Class 1 anti-magnetic resistance (4,800 A\/m), the movement defends timekeeping precision against everyday magnetic fields from laptops and mobile devices, maintaining a reliable factory static tolerance of -20 to +40 seconds per day. The case is engineered with substantial, contemporary sports-dress proportions, measuring an official 41.0mm in case diameter with a case profile thickness of 11.7mm, an interhorn lug width of 22.0mm, and a total weight of approximately 141.0 grams. The watch sits exceptionally balanced on the wrist, offering a solid, reassuring heft that speaks to its all-metal construction and refined finishing. The solid 316L stainless steel case architecture combines vertical hairline satin brushing across the upper lug surfaces with mirror-polished flanks and beveled contours. Dial protection is provided by a heavy-duty, impact-resistant flat mineral crystal glass. The reverse side features an exhibition see-through screw-down caseback that allows the wearer to view the mechanical movement, decorated oscillating rotor, and jewel pivots from behind. Built for dependable daily active resilience, the solid stainless steel case features an ergonomic fluted push-pull crown at 3 o'clock, securing a certified 10-bar (100 meters \/ 330 ft) water resistance rating, making it completely safe for swimming, snorkeling, water sports, and daily active wear. The timepiece comes completed on an integrated solid stainless steel multi-link construction featuring alternating satin-brushed and polished links, secured by a sturdy fold-over deployment clasp with dual push-button safety release.\u003c\/p\u003e","brand":"MonaWatch","offers":[{"title":"Default Title","offer_id":67758820884794,"sku":"NH9150-52E","price":920.0,"currency_code":"AED","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0920\/5858\/3354\/files\/NewProject_00e810f2-c1fa-4bb1-858b-36b6d8df8dc9.webp?v=1792647378","url":"https:\/\/www.monawatch.com\/products\/citizen-collection-open-heart-nh9150-52e-mens-watch","provider":"MonaWatch","version":"1.0","type":"link"}