Rolex · Day-Date 36

Strap for Day-Date 36 Yellow Gold Diamonds / Oyster / Black Diamonds Rubies

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter36 mm
Reference118388-0191
FamilyDay-Date 36
MovementRolex caliber 3155 Hours, Minutes, Seconds | Date, Day | Chronometer
CaseYellow Gold

Recommended spring bar

Spring bars Rolex Daytona 116520 — 20mm steel

Technical match for lug width and diameter · lug 20 mm · Ø 1.5 mm · closed lugs

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Straps for the Day-Date 36 118388-0191

Selected for the 20 mm lug width · workshop selection

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The Day-Date 36 118388-0191, seen from the bench

The Day-Date 36 uses the automatic Rolex caliber 3155 with chronometer certification, which displays hours, minutes, seconds, date and day of the week. The case has a diameter of 36mm with 20mm lugs. The movement offers complete time indications with dual calendar complication.

Frequently asked questions

What is the exact lug width of the Rolex Day-Date 36 reference 118388-0191?

The lug width of the Rolex Day-Date 36 reference 118388-0191 is precisely 20mm. This is measured between the inner lugs of the case. It is absolutely critical to verify this measurement before purchasing a strap: a strap that is too narrow (18mm) will move excessively, whilst one that is too wide (22mm) will not fit at all. Use a ruler or calliper to measure from lug to lug internally.

Which strap pairs best with the Day-Date 36 in yellow gold?

Alligator leather in black is the timeless choice for the Day-Date 36 in yellow gold with champagne dial. It creates elegant contrast without visual noise. If you prefer warm tones, tobacco brown or chocolate brown in vegetable tanning accentuate the warmth of the gold beautifully. For depth of character, deep burgundy with matching stitching offers personality whilst maintaining classicism. Avoid vibrant or neon shades, which would undermine the equilibrium of the piece.

How do I change the strap on a Rolex Day-Date 36?

Strap replacement requires a spring bar tool to compress and release the horizontal pins of the case. Position the flat end of the tool in the small groove of the pin, press gently inward to create space, then remove the existing strap. Repeat for the opposite side. Insert the pins of the new strap into the case lugs and ensure both pins seat fully. If uncertain, entrust the work to an experienced watchmaker.

Can I use a non-Rolex aftermarket strap on my Day-Date 36 118388-0191?

Yes, provided it has the correct 20mm lug width. Artisanal straps in alligator, calf or shell cordovan from specialist leather workers often exceed the quality of official Rolex aftermarket options, with superior colour and finish variety. Ensure the strap features Rolex-compatible spring bars (typically 1.80mm diameter) and that the craftsperson has proven experience with luxury watches.

What is the typical lifespan of a leather strap for a Rolex Day-Date 36?

Longevity depends upon material and daily use patterns. An alligator strap with vegetable tanning typically lasts 3–5 years in daily wear, developing a noble patina over time. Boxcalf is slightly less durable (2–4 years) but offers superior comfort. Shell cordovan, owing to the density of equine fibre, can last 5–7 years even under demanding conditions. Regular maintenance—gentle cleaning, proper drying, and occasional conditioning—significantly extends strap life.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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