What the SRPD 5 Sports family shares
The SRPD 5 Sports family has 15 models with their own pages. Each row is Seiko's product data for that reference; "Seller claims" counts the sold parts that name it.
| Model | Movement | Between lugs | Case diameter | Seller claims |
|---|---|---|---|---|
| SRPD51 | 4R36 | 22 mm | 42.5 mm | none in the catalogue |
| SRPD53 | 4R36 | 22 mm | 42.5 mm | none in the catalogue |
| SRPD55 | 4R36 | 22 mm | 42.5 mm | 9 parts |
| SRPD57 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD59 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD61 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD63 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD65 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD71 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD73 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD76 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD77 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD79 | 4R36 | 22 mm | 42.5 mm | 6 parts |
| SRPD93 | 4R36 | 22 mm | 42.5 mm | none in the catalogue |
| SRPD95 | 4R36 | 22 mm | 42.5 mm | none in the catalogue |
Do not read a shared number as a shared case: the figures above are outside dimensions and the movement name. They say nothing about bezel seats, crystal seats or the movement holder, which is why the part claims below matter.
SRPD51 specifications
The SRPD51 has no seller claim in our catalogue. These are Seiko's figures for it:
Seiko SRPD51, from Seiko’s product page
Against the SRPD55 that most sellers name, the SRPD51 shows the same movement, diameter and lug distance (case 13.4 mm thick). That is a reason to expect parts listed for the SRPD55 to be relevant, not a certificate that they fit.
Parts and seller links
9 sold parts name at least one SRPD 5 Sports reference. Each row is the seller's claim about its own part, with the seller's page linked and a footnote to our copy of it. Quotes and dates for each reference are on the parts compatibility tool.
| Part | Type | Seller says it fits | Conditions | Seller page |
|---|---|---|---|---|
| SKX007/SRPD Flat Ceramic Bezel Insert - Black/White/Red - CT651 | Bezel insert · CT651 | SRPD55, SRPD57, SRPD59, SRPD61, SRPD63, SRPD65, SRPD71, SRPD73, SRPD76, SRPD77, SRPD79 | None stated | Crystaltimes23 |
| SKX007/SRPD Flat Ceramic Bezel Insert - CT656 | Bezel insert · CT656 | SRPD55, SRPD57, SRPD59, SRPD61, SRPD63, SRPD65, SRPD71, SRPD73, SRPD76, SRPD77, SRPD79 | None stated | Crystaltimes24 |
| SKX007/SRPD Sloping Bezel Insert – Silver/Black SKX Style – CT6135 | Bezel insert · CT6135 | SRPD55, SRPD57, SRPD59, SRPD61, SRPD63, SRPD65, SRPD71, SRPD73, SRPD76, SRPD77, SRPD79 | None stated | Crystaltimes25 |
| SKX007/SRPD Steel Bezel Insert: SMP style | Bezel insert | SRPD55 | Seller explicitly lists SRPD55K1, SRPD55K2 and SRPD55K3. | namokiMODS26 |
| SKX007/SRPD Knurled Bezel: Polished Black Finish | Bezel | SRPD55 | Seller explicitly lists SRPD55K1, SRPD55K2 and SRPD55K3. | namokiMODS27 |
| SKX007/SRPD Chapter Ring: Numerals Style Silver Finish | Chapter ring | SRPD55 | Seller explicitly lists SRPD55K1, SRPD55K2 and SRPD55K3. | namokiMODS28 |
| SKX007/SRPD/SSK GMT Double Dome Sapphire Crystal for flat bezel inserts - CT037F | Crystal · CT037F | SRPD55, SRPD57, SRPD59, SRPD61, SRPD63, SRPD65, SRPD71, SRPD73, SRPD76, SRPD77, SRPD79 | None stated | Crystaltimes29 |
| SKX007/SRPD/SSK GMT Double Dome Sapphire Crystal for sloping bezel inserts - CT037CIS | Crystal · CT037CIS | SRPD55, SRPD57, SRPD59, SRPD61, SRPD63, SRPD65, SRPD71, SRPD73, SRPD76, SRPD77, SRPD79 | None stated | Crystaltimes30 |
| Seiko 5 Sports SRPD 5KX SSK GMT Crystal Gasket - CT419 | Gasket · CT419 | SRPD55, SRPD57, SRPD59, SRPD61, SRPD63, SRPD65, SRPD71, SRPD73, SRPD76, SRPD77, SRPD79 | None stated | Crystaltimes31 |
Named SRPD, claim for another watch: NMK801 FKM Curved End SKX/SRPD Rubber Strap: Black. The rows we hold for it name SKX007 only, so for an SRPD the fit is unknown.
The crown at 4
Reports put the SRPD crown at 4 o'clock, as on the SKX. Our evidence: a reviewer's measurement records the SKX007 crown at 4 o'clock3measured, and a review of the SRPD67K1 says the crown is at 4 o'clock with the case sides extending out as crown guards.2 The SRPD67K1 has no page of its own here and our SRPD51 and SRPD55 pages have no crown field, so treat 4 o'clock as the likely layout and confirm it on your case.
It decides two parts. A seller sets the dial feet for either a 3 or a 4 o'clock crown, so a dial must be oriented for 4; and the same seller sells the day-date NH36 in a separate 4 o'clock crown version, because the day wheel is set for one position.1
Lug width and strap
Seiko gives 22 mm between the lugs for all 15 models in the table above, and 46 mm lug to lug for the SRPD514. See every watch with this width on the 22 mm lug-width page. The strap listed in our catalogue with a 22 mm lug width is named for the SKX007, with a seller condition about spring bars (see the parts table). Whether it fits an SRPD end-link is not stated. Check the strap's thickness and the lug-hole depth too; a width alone does not settle it. The strap size tool lists what the data holds.
Movement
Seiko fits the day-date 4R36 (see its page for Seiko's ratings). The SKX007 has a 7S26. For a swap, the day-date counterpart from TMI is the NH36; the NH35 guide compares it with the NH35, 4R35 and 4R36 on the figures that matter for hands and dials.
| Figure | SRPD55 | SKX007 |
|---|---|---|
| Movement | 4R366 | 7S267seller listing |
| Case diameter | 42.5 mm8 Sources disagree: manufacturer 42.5 mm / measured 41 mm9 | 42.5 mm3measured Sources disagree: measured 42.5 mm / measured 42 mm10 |
| Lug to lug | 46 mm8 | 46 mm3measured |
| Thickness | 13.4 mm8 Sources disagree: manufacturer 13.4 mm / measured 13 mm9 | 13.25 mm3measured Sources disagree: measured 13.25 mm / measured 13 mm10 |
| Between lugs | 22 mm8 | 22 mm3measured |
| Water resistance | 10 bar8 | 200 m7seller listing |
Checklist before you buy
- Read the full reference on the caseback (for example SRPD51K1) and find it in the parts table. No row means unknown.
- Open the seller's page and compare its fit list with your reference, not only with the family name.
- Confirm the crown at 4 on your case before buying a dial, a day-date movement or any part that depends on the crown side.
- For a strap, measure the distance between your lugs; Seiko gives 22 mm for the models above. Check spring-bar and end-link shape.
- For a bezel insert or crystal, ask whether the seller lists your reference and whether the insert type (flat, sloping) matches the crystal profile.
- Keep the original parts. After any crystal, gasket or case change, have the water resistance tested before water exposure.
The 3D builder previews a combination of these parts; it does not approve dimensions. The SKX family page lists the older cases many of these parts were made for.