Seiko Mod Parts: Movements, Case Backs, Gaskets & Small Parts

Seiko Mod Parts That Finish a Build

The movement, the case back and the small parts that close up a Seiko mod build. Each part names the watch, case or movement it's made for.

What's Here

• Movements: Seiko (TMI) NH35A, NH36A, NH38A, NH34A GMT and NH71, each with hacking and hand-winding and an uncut stem.
• Case backs: sapphire to show the movement, or sterile, standard or slim, for the SKX007 case and our replacement cases.
• Rotors: decorative rotors for 4R, 7S, NH and NE movements, to show through a sapphire case back.
• Day and date wheels: NH36A kanji day wheels for a 3 o'clock or 3.8 o'clock crown, and NH35/NH36 date wheels.
• Gaskets: glass, bezel and case back gaskets, each for the watch it names.
• Spring clicks: for the SKX007, SKX013 and SRP Turtle Re-issue, and a bi-directional click that lets the SKX007 or SRPD bezel turn both ways.
• Spring bars, clasps and buckles: fat and slim spring bars, a V-clasp, a wetsuit ratchet clasp, a Sub divers clasp and bronze buckles.
• Also here: Rodico for dust and fingerprints on dials and hands, a stem for the NH movement, an endlink for our Seamaster-style cases, and our laser engraving service.

Frequently Asked Questions

Which movements are here?

The Seiko (TMI) NH35A, NH36A in 3 o'clock and 3.8 o'clock crown versions, NH38A, NH34A GMT and NH71.

Which gasket do I need?

The one that names your watch or case. The glass, bezel and case back gaskets here each name what they're made for, from the SKX007 and SKX013 to the SRP Turtle Re-issue, SRPD, SSK and SRPE.

Can I make my bezel turn both ways?

On an SKX007 or SRPD, yes, with the SKX007/SRPD Bi Directional Spring Click.

Which spring bars do I need?

The fat spring bars fit the wider lug holes of the SKX007 and similar diver cases. The Seiko 5 GMT SSK and the SRPD take the slim spring bars.

Browse the parts above to find the one for your build.