AnchorFlex™ End-Link
Integrated look. Everyday simplicity.
Fits the Seiko 5 Sports Field series with our own machined 316L end links, for a case-hugging profile and the simplicity of a traditional buckle.
Everything you need is in the box — end links and premium 1.8mm spring bars included.
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: 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
This is a 2-piece strap, sized 80mm and 120mm. It's the strap you leave on.
Specifications
- Material — AnchorFlex™ FKM rubber
- Buckle — 316L stainless steel
- End links — Custom machined 316L, included
- Spring bars — Premium 1.8mm, included
- Fits — Seiko 5 Sports Field series, 20mm lug width
- Length — 2-piece: 80mm and 120mm sides, Fits 6.25-8in 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.
