The Seiko Prospex Marinemaster Limited Edition 44.3mm (Ref. SLA047J1) draws inspiration from Iriomote island’s verdant nature through rich forest green dial whilst representing a contemporary reinterpretation of the famous 1968 Hi-Beat diver. Limited to 3,000 pieces worldwide, this is hand-assembled at the Shizukuishi Watch Studio in Morioka alongside mechanical Grand Seiko watches, with the top-of-the-line 8L35 calibre created specifically for professional diver’s applications.

At 44.3mm with 15.4mm thickness through stainless steel monobloc case construction with super-hard coating, this provides substantial professional diving presence whilst the unusual monocoque case architecture contributes to the exceptional 300m water resistance suitable for both saturation and scuba diving. The ceramic bezel insert provides superior scratch resistance whilst the forest green dial with lume plot beside the date window creates distinctive character within the Marinemaster lineage.

The Calibre 8L35 delivers reliable 50-hour power reserve through eight alternations per second construction with 26 jewels, essentially a simpler version of the Grand Seiko 9S55 movement, ensuring exceptional accuracy from a movement purpose-built for professional diving applications. The hand assembly and adjustment by Shizukuishi’s skilled craftsmen validates the top-of-the-line positioning.

The stainless steel bracelet with super-hard coating provides durable everyday wear whilst the additional silicone strap offers a practical alternative. The 300m rating with monobloc case construction ensures genuine professional saturation diving capability. The SLA047J1 occupies the same space as the Marinemaster 300 but with Iriomote green and a 3,000-piece worldwide allocation, making it a meaningful collector’s piece within the Prospex hierarchy.