Sinn EZM 3 (not bead-blasted finish, but compatible)
Expected by Mon 24 November when you select Express Delivery at checkout
YOUR BRACELET IS NEVER THE PERFECT FIT
Sinn makes some of the toughest, most capable tool watches in the world — but even they missed this. Add it, and it’s perfect.
Morning: perfect. Afternoon: too tight. Evening: too loose. Heat, cold, and movement change your wrist — your bracelet can’t keep up.
On The Fly fixes that with instant, tool-free ±5 mm adjustment, completely hidden under your clasp. You’ll never see it, and neither will anyone else — except they’ll notice your watch always sits perfectly.
Always Perfect – Comfort on demand, in seconds.
Invisible Upgrade – Discreetly tucked under the clasp, preserving your watch’s original look.
Luxury Craftsmanship – Same high-grade stainless steel as Sinn, with a flawless aesthetic match.
Easy 1-Minute Install – Uses your existing screw and hex key; install once and adjust forever.
Reversible – Install once, remove anytime, no trace.
Once you try it, every other bracelet will feel wrong.
We offer reliable worldwide shipping, and orders are carefully processed and dispatched with tracking details provided. If for any reason you are not satisfied with your purchase, you may return it within 14 days of receipt, provided the item is unused, in its original packaging, and in resalable condition. Please note, we cannot accept returns for used items. Refunds or exchanges will be processed once the return has been received and inspected.
All Steel Reef products come with a comprehensive 3-year warranty, covering manufacturing defects in materials and craftsmanship under normal use. If an issue arises within this period, simply contact our team and we will repair or replace the item at no additional cost. This warranty reflects our commitment to quality and ensures peace of mind with every purchase.
Every Steel Reef component is precisely engineered and thoroughly inspected.
In the rare event of a manufacturing fault or a genuine fit issue, we’ll take care of it with a replacement.
Have questions about sizing, compatibility, or choosing the right accessory? Our team of specialists is here to help. Reach out anytime for personalized advice and expert guidance to ensure you select the perfect product for your timepiece.
Sinn 'On the Fly' Folding Extension H-Link
Overview
Specifications
Our Values
3,000+ Customers worldwide
Trusted by collectors across every continent. Owners who value authenticity choose Steelreef. Proven upgrades, worn daily on thousands of wrists.
SWISS PRECISION MANUFACTURING
Cut, finished, and tolerance-tested in Switzerland. Every edge, curve, and click meets factory spec. Precision isn’t a claim — it’s our process.
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Secure, insured delivery to your door. No compromises, no uncertainty, wherever you are. Engineered upgrades, shipped with confidence worldwide.
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We build what collectors ask for. Your insights shape our engineering roadmap. Every release solves a real wrist-level challenge.
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DarrylW
Fits and Looks OEM!
The on-the-fly link is the perfect accessory to my vintage “meters first” 5513. The bracelet now fits perfectly in warm or cold weather. Before, it had to be compromise-adjusted to be too loose for warm and a bit tight for cold. The link material and finish match perfectly also, and indistinguishable from OEM.
Submariner "On the Fly" Extension Link
Jason T.
Fits perfectly
The extension link was easy to install and fits my Tudor Heritage Chrono perfectly. No more tight fit. I will buy for some of my other watches.
“On The Fly” Extension Link - Micro Adjustment for Longines Spirit Models
Matt
Awesome as always! This is my third one!
Explorer “On the Fly” Extension Link
Tom
Finish and in all aspects identical to the rest of the bracelet.
