316L stainless steel construction ensures durability and corrosion resistance
Polished finish provides a sleek, professional appearance
Double domed sapphire crystal with blue AR coating enhances clarity and scratch resistance
20 ATM water resistance supports a range of activities
Customizable with customer-selected bezel, crown, bracelet, and gaskets for tailored builds
This is a 3 o'clock case various Seiko movements including the NH35. The case has a 37.4mm diameter when fully assembled and very similar to the SKX023 cases. While it does take design cues from the SKX023, the parts are not compatible. This item now comes with a customer selected bezel, crown, and bracelet option along with the appropri
Case Material
316L stainless steel
Case Diameter
37.4 mm (with bezel)
Case Thickness
12.1 mm (with bezel at edge)
Lug to Lug Height
44.7 mm
Lug Width
20 mm
Caseback
Screw-down, solid polished finish
Water Resistance
20 ATM (with proper assembly)
Crystal
Double domed sapphire, blue AR coating on underside
Included
Case with installed double domed sapphire crystal, gaskets, clickspring (if needed)
5.0
5 ratings
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1
Very happy with the case. High quality for a very awaited project. Great finishings, measurement super correct to average wrists, and the visible surface of the dial without distortion due to a great crystal allows an unlimited combination of dials, styles and colors.
A
Alejandro · April 19, 2026
Fantastic mid-size case for Seiko NH parts. The thinness, quality, fit and finish are the best I’ve seen. Would recommend for anyone considering <40mm case sizes for seiko modding. Fits well with SRPE bracelets.
A
Anonymous · March 22, 2026
Great QC, AJ’s watch parts just fit: the first time, every time. The DCP231 results in a consistent build that you will be proud to show friends or give as a gift to someone special.