70 products
Seiko Mod Tools & Miscellaneous Parts
Find the tools, movements, and small parts that complete a Seiko mod build at Watch&Style. This collection gathers the components that don't fit the main part categories but are essential to finishing a build — automatic movements, case backs, gaskets, spring bars, rotors, day and date wheels, spring clicks, stems, and clasps. Whether you're assembling a build from scratch or replacing a worn component, this is where you find the supporting parts.
What's in the Collection
The collection covers the practical components of a build. Seiko (TMI) automatic movements — NH35, NH36, NH38, and NH34 GMT — power the build. Sapphire and sterile case backs (in slim and thick profiles) close it. Gaskets (glass, bezel, case-cover, rotating-bezel) keep it sealed. And the smaller essentials — spring bars, spring clicks, NH stems, movement rotors in several finishes, day and date wheels, clasps, and buckles — handle the details that make a build work.
Fitment & Compatibility
Many of these parts are platform-specific — gaskets, case backs, and spring clicks are sized for particular cases (SKX007, SKX013, SRP Turtle, SRPE), so check the Models filter and product details against your build before ordering. Movements (NH35/NH36/NH38/NH34) fit the standard Seiko mod case footprint. Pair these parts with your case, crystal, and dial to complete the build.
Frequently Asked Questions
What's the difference between the NH35, NH36, NH38, and NH34 movements?
The NH35 is a date-only automatic; the NH36 adds a day-date complication (available in 3 o'clock and 3.8 o'clock crown variants); the NH38 is a no-date version for clean dials; and the NH34 is the GMT movement for travel-watch builds. All share the standard Seiko mod mounting footprint — choose based on the complication your build needs.
Do I need a specific gasket for my case?
Yes. Gaskets are sized per platform — an SKX007 glass gasket won't fit an SRPE or SRP Turtle. Match the gasket to your case using the product details, and replace gaskets when swapping crystals or case backs to maintain water resistance.
What's a spring click, and when do I need one?
The spring click (or bezel spring) is the small part that creates the clicking action and holds the rotating bezel in place. If your bezel feels loose or doesn't click properly, replacing the spring click can restore the action. Match it to your platform.
Browse the full tools and parts collection above to find the components that complete your build.