Seiko Mod SKX007 Square 42mm - Build 02

Square SKX007-Inspired Custom Watch

This Rexx workshop build takes the familiar language of an SKX007-style diver and places it inside a distinctive square 42mm case. The result keeps the practical character of a mechanical sports watch while giving the case, dial, and rubber strap a much less conventional profile.

This is an independent custom build rather than a factory Seiko model. It is assembled and checked by Rexx Timepieces using an NH35A automatic movement and a carefully matched set of aftermarket components.

Built Around the NH35A

Inside is the Japanese NH35A automatic movement, a widely used mechanical calibre valued for straightforward operation and practical serviceability. The transparent caseback gives a direct view of the movement and makes the mechanical construction part of the watch's character.

Square Case, Diver Character

The 42mm stainless-steel case has a stronger geometric presence than a conventional round diver. Sapphire crystal protects the dial, while the rubber strap keeps the watch purposeful and suited to its sport-watch direction. The stated water-resistance rating is 10 ATM; as with any mechanical watch, seals should be checked periodically if the watch is regularly exposed to water.

Verified Specifications

• Movement: Japanese NH35A automatic
• Case: 316L stainless steel
• Case width: 42mm, excluding the crown
• Crystal: Sapphire crystal
• Caseback: Transparent exhibition back
• Strap: Rubber
• Water resistance: 10 ATM stated rating

Watch the Full Build

The complete workshop build is documented on the Rexx Timepieces YouTube channel. It provides useful hands-on context beyond the finished product photographs.

Explore more Seiko mod builds, read Rexx Knowledge and Guides, or discuss a different direction through Rexx custom watch projects.

Rexx Timepieces is an independent workshop. This custom build is not manufactured, sponsored, or endorsed by Seiko.