BLK's latest Rolex Yacht-Master series in 40mm/42mm features a calendar that supports both forward and backward adjustments! The window distance is customized with the exclusive 3235 integrated movement, ensuring stable and reliable performance. Quality assurance: .1. Case: The dimensions and thickness match the original, unlike market versions that are easily identifiable as fakes.2. Dial: Top-quality Swiss ice blue luminous material with a delicate texture and accurate colors; it boasts exceptional moonlight-truly the king of the night! .3. Glass: Sapphire glass combined with a 2.5x magnifying effect, offering excellent transparency and clearer fonts.4. Strap: Fluoroelastomer strap, perfectly fitting with the lugs for maximum wrist comfort; orders for the welfare strap version come with a complimentary natural rubber strap-definitely a premium product. Every exquisite detail is crafted with BLK's dedication and ingenuity. First-class workmanship, identify with BLK's unique serial number and design. Quality guaranteed, high-quality, high-end product!