The size is simply your wrist measurement. Measure your wrist, round to the nearest centimetre, and pick that number. We cut each bracelet 3cm longer than the wrist it is made for, so it sits close without gripping.
Find your size
Your wrist measures
Pick
14.5 - 15.4 cm5.7 - 6.0 in
15
15.5 - 16.4 cm6.1 - 6.4 in
16
16.5 - 17.4 cm6.5 - 6.8 in
17
17.5 - 18.4 cm6.9 - 7.2 in
18
18.5 - 19.4 cm7.3 - 7.6 in
19
19.5 - 20.4 cm7.7 - 8.0 in
20
Tap a row to choose that size
Measure the wrist itself rather than another bracelet. Bracelets are cut to different lengths, so copying one rarely lands on the right size.
Measuring guide
Cut a strip of paper or take a length of string and wrap it once around the base of your wrist, over the wrist joint where it is thickest.
Mark the point where the end meets the strip with a pen.
Lay the strip flat against a ruler and read the length in centimetres or inches.
Measuring tips
Keep the strip snug against the skin but not tight. That reading is your wrist circumference.
Left and right wrists differ slightly. Measure the one you will wear it on.
For a looser fit, take one size up. The bracelet is already cut 3cm longer than your wrist.
★★★★★4.8 / 5 - 4,791 Verified Buyers
Bundle & Save
2 for $39 · 3 for $49 - Today Only
The Serment
A bracelet that locks on, not clasps
Serment means oath. This is the bracelet built around that idea: a slim, screw-fixed cuff that goes on once and stays on. No catch to fidget with, no clasp to spring open in a coat sleeve. It fastens with two screws and a matching screwdriver, and then you simply forget about it.
Screw-fixed closure. Fitted once with the included driver, then worn continuously.
Slim 4mm profile that sits flat under a cuff and stacks with a watch.
Three golds, six sizes. Rose, white and yellow, in wrist sizes 15cm through 20cm.
Driver and travel case included. Nothing else to buy.
The Serment
Made to be worn, not managed
Most bracelets are a small daily negotiation: clasps that catch on sleeves, chains that slide, links that need a jeweller. The Serment removes all of it. Two screws draw the cuff closed against the wrist, the head sits flush with the surface, and the whole thing measures 4mm across so it disappears beneath a shirt cuff. It is built for the person who puts something on and does not want to think about it again, through showers, gym sessions and airport security.
Fitted in under a minuteSits flat beside a watch
Three Golds
Rose reads warm and softens against most skin tones. Yellow is the traditional choice and the one that reads richest in low light. White gold is the quietest of the three, closer to steel, and the easiest to wear alongside a silver watch. All three carry the same ring motif and the same mirror-polished finish.
Rose, white and yellow4mm across
“Put it on in January and haven’t taken it off since.”
Marcus T. - Verified Buyer
Six sizes, made for both of you
Specifications+
StyleScrew-fixed cuff bracelet
Width4mm
Wrist Sizes15, 16, 17, 18, 19 and 20cm
Bracelet LengthYour wrist size plus 3cm
FinishMirror-polished throughout
ColoursYellow Gold, White Gold, Rose Gold
ClosureTwin screw fixing, flush heads
IncludedMatching screwdriver and presentation case
Water ResistanceSplash and shower safe
Questions & Answers+
Which size should I order?
The size is your wrist, not the bracelet. Wrap a strip of paper around your wrist, mark where it meets, measure it flat against a ruler, round to the nearest centimetre, and pick that number. We cut every bracelet 3cm longer than the wrist it is made for, so it sits close without gripping. Between two sizes, or if you want it looser, take the larger one.
How do the bundles work?
One bracelet is $29. Two are $39, and three are $49. Mix any of the three colours and any of the six sizes you like. The discount applies automatically in your cart, with nothing to enter.
Is it the same bracelet for men and women?
Yes. The design is unisex and the six sizes cover most adult wrists. Men usually measure 17cm to 20cm and women 15cm to 17cm, but measure rather than guess, it takes a minute.
Do I need a jeweller to put it on?
No. The driver is in the box. Line the cuff up on your wrist, turn each screw until it sits flush, and that is it. It takes under a minute, and it is just as easy to take off again.
Can I shower and swim with it?
Showering, washing and rain are all fine. We would keep it out of chlorinated pools and salt water, which dull the finish on any plated piece over time.
Is it affiliated with any luxury brand?
No. The Serment is an independent Umbraux piece inspired by the screw-fixed bracelet form. It carries our own branding and is not associated with any other maker.
Will the colour wear off?
Worn daily and kept away from chlorine and perfume, the finish holds well. Wipe it with a dry cloth now and then. If yours fades inside 30 days, contact us and we will replace it.
Shipping & Delivery+
Free shipping on all orders. Orders are processed within 1 to 3 business days. Estimated delivery is 10 to 20 business days depending on your location. Tracking is emailed as soon as your order ships.
Returns+
30-day return policy. If the fit or the finish is not right, contact support within 30 days of delivery and we will arrange a refund or exchange. Items must come back in their original condition with the driver and case.
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