AnchorFlex™ Flagship EL for Seiko SRPG - Sea Moss Green - Anchor Strap Co.

AnchorFLEX™ End-Link Deployant

For Seiko SRPG Series field watches

A complete integrated rubber upgrade for the Seiko SRPG series field watches, built with fitted stainless steel end links.

Made for the Seiko SRPG series field watches
End links included for a clean integrated fit
Durable FKM rubber with a soft, flexible feel
Designed for daily wear, travel, and water use

Shipping calculated at checkout.

Material: AnchorFLEX™ FKM rubber

Included Hardware: Custom-milled 316L stainless steel end links and premium 1.8mm spring bars.

Compatible with the Standard Precision Deployant Clasp

Fitment: Designed for the Seiko 5 Sports Field 39.4mm SRPG/SBSA case family. Not compatible with other Seiko 5, Prospex, SKX, Turtle, Samurai, Alpinist, GMT, or 36mm field models.

SRPG27
SRPG29
SRPG31
SRPG33
SRPG35
SRPG37
SRPG39
SRPG41

Length: 3-piece strap with 2 clasp ends (75mm/100mm) and one hole end (105mm) for maximum flexibility. Comfortably fits wrists from 5.25" to 8"

AnchorFlex™ End-Link Deployant

Integrated look. Clasp-secured confidence.

Fits the Seiko 5 Sports Field series with our own machined 316L end links, for a case-hugging profile that closes with a deployant clasp instead of a buckle.

End links and premium 1.8mm spring bars are included. Clasp not included unless selected at checkout.

Fits: SRPG27, SRPG29, SRPG31, SRPG33, SRPG35, SRPG37, SRPG39 — Seiko 5 Sports Field, 39.4mm case. Also sold in Japan under SBSA references. Does not fit: SSK023 and related Seiko 5 Sports GMT field models, SRPJ81 / SRPJ83 / SRPJ85 (36mm, 18mm lugs), or SRPD SKX-style models.

Machined end links, made for this watch

Same geometry as the AnchorFlex Flagship, our original rubber strap — re-engineered for end-link compatibility so it sits flush against the case.

We machine the end links in 316L stainless, shaped to the Field case so the transition from case to strap looks like it came that way from the factory. No extra hardware needed.

Every strap ships with our Premium 1.8mm spring bars, machined to seat cleanly so installation goes smoothly the first time.

Why FKM

FKM fluoroelastomer is what we build every AnchorFlex strap from, and it's why they last:

Holds up to UV, heat, and chemicals
Won't crack, fade, or go brittle with age
Soft and pliable against the wrist, but structured enough to keep its shape
No sagging or collapse the way cheap rubber does

Profile

Clean modern lines with a subtle taper
Substantial enough for daily wear, refined enough to dress up
Built to complement a tool watch, not overpower it

Precision Deployant Clasp: optional add-on

The strap's clasp ends are made for our 18mm Precision Deployant Clasp — the same clasp used across the AnchorFlex deployant line. Add it at checkout, or pair the strap with one you already own.

18mm, 316L stainless steel in a brushed and polished finish
Secure closure with no loose tail
Easy on and off, with no threading and no wear from repeated buckling

Your fit, right out of the box

There's no size to choose at checkout. Every strap ships with three pieces: two clasp ends and one hole end. Pick the pairing that fits your wrist, then fine-tune at the clasp.

It's the strap you leave on.

Specifications

Material — AnchorFlex™ FKM rubber
Clasp — 18mm Precision Deployant, brushed/polished 316L. Optional add-on, sold separately.
End links — Custom machined 316L, included
Spring bars — Premium 1.8mm, included
Fits — Seiko 5 Sports Field series, 20mm lug width
Length — 3-piece: two clasp ends (75mm / 100mm), 105mm hole end. Fits 5.25″–8″ wrists.
Profile — Slim and flexible for all-day wear

FAQs

Some end-link installs can feel tight at first because the thickness rubber strap at the end-link is maximized to ensure durability. There are a few ways to get it installed:

First, try gently wiggling and pushing the spring bar through until the spring bar pops into the opposite side of the end link. This can require some effort.

You can also squeeze the rubber portion of the strap into the end link between your thumb and index finger while pushing the spring bar into place. This helps compress the rubber slightly and gives the spring bar more room to seat properly.

If those techniques do not work, our premium 1.7mm spring bars can be used as an alternative. There is no downside to using them, but we recommend trying the first two installation methods first since the standard spring bars usually work once everything is seated correctly.

If you still have trouble, contact us and we can help troubleshoot the install.

AnchorFLEX™ straps are made from premium FKM rubber and have been third-party tested to be free of harmful fluorinated “forever chemicals” within the scope of the testing performed. We do not intentionally add PFAS-based coatings, surface treatments, or chemical finishes to our straps. Because FKM is a fluorinated rubber, we avoid vague blanket claims and clearly disclose the material. Customers who prefer to avoid fluorinated rubber entirely may prefer our nylon, sailcloth, leather, or other non-FKM strap options.

AnchorFlex™ End-Link Deployant for Seiko SRPG Field Watches - Sea Moss Green