【Replacement 40.5mm Stainless Steel Sub Case for NH35/NH36 – Diver Watch Case with Sapphire Crystal】 – Precision-engineered replacement watch case designed for Seiko NH35 and NH36 automatic movements. Features 40.5mm diameter (excluding crown)-– the classic Submariner-inspired size for versatile mod builds. Crafted from solid stainless steel with a premium brushed finish-. Equipped with a scratch-resistant sapphire crystal – offering superior clarity and durability far beyond mineral glass-19. The essential foundation for your custom diver watch project.
Precision Fit for NH35/NH36 & Compatible Movements – Specifically engineered for Seiko NH35, NH36, 4R35, and 4R36 automatic movements-3. Also compatible with NH34, 7S26, 7S36, ETA2824, and PT5000 movements-12. The case accepts 28.5mm dials – the standard size for NH35/NH36 builds. The 20mm lug width--19 accommodates most aftermarket straps and bracelets.
Premium Stainless Steel – Built for Durability – Crafted from solid
stainless steel – the industry standard for premium dive watch cases. Key advantages:
Superior corrosion resistance – withstands saltwater, sweat, and daily wear-12
Brushed and polished finish – matches the premium Submariner-style aesthetic-
Screw-down crown – ensures secure water resistance up to 200 meters-19
Solid construction – no hollow or stamped parts – premium weight and feel
Sapphire Crystal with AR Coating – Clarity That Lasts – Features a scratch-resistant sapphire crystal with anti-reflective (AR) coating-19. Unlike mineral glass that scratches easily, sapphire maintains pristine clarity even after years of use-12. The calendar magnifier (cyclops) at 3 o‘clock provides easy date reading-. Available in flat or domed profiles to match your build style.
Complete Modding Foundation – Everything You Need – This case kit typically includes:
40.5mm 316L stainless steel case – with sapphire crystal pre-installed
Screw-down crown – with correct stem height for NH35/NH36 movements
Case back – solid or exhibition (透底) options available-3
Ceramic bezel insert – 60-minute unidirectional dive scale--19
Waterproof gaskets – pre-installed for 200m water resistance
Complete set – ready for your NH35 movement and 28.5mm dial
The Ultimate Seiko Mod Foundation – The 40.5mm Sub case is one of the most popular platforms in the Seiko modding community. Why choose this case?
Classic proportions – 40.5mm diameter, 13mm thickness, 48mm lug-to-lug-
Versatile design – works with ceramic, aluminum, or steel bezel inserts
200m water resistance – ready for real-world diving-19
Perfect for custom builds – pair with NH35/NH36 movements and 28.5mm dials
OEM-spec quality – precision-machined to match professional watch standards
Professional-Grade Aftermarket Alternative – Precision-crafted to match OEM specifications. A cost-effective solution compared to sourcing factory cases. Available in multiple finishes – silver, black PVD, and gold PVD options. Note: These are aftermarket replacement parts, not genuine Seiko® parts. However, they are engineered to the same specifications as professional-grade diver watch cases.
stainless steel – the industry standard for premium dive watch cases. Key advantages:
