Rolex · Day-Date 36

Strap for Day-Date 36 Yellow Gold Diamonds / President / Champagne Diamond

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
Reference118388-0046
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 118388-0046

Selected for the 20 mm lug width · workshop selection

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The Day-Date 36 118388-0046, seen from the bench

The Rolex Day-Date 36 118388-0046 in yellow gold embodies 68 years of classical watchmaking heritage. Introduced in 1956 as the first automatic chronograph displaying hour, date, and day simultaneously, this model maintains aesthetic authority through refined proportions. The 36 mm yellow gold case houses the Rolex 3155 automatic movement, certified chronometer with antimagnetic Parachrom hairspring. The Champagne sunburst dial features stick indices and date window. Water-resistant to 100 metres with Twinlock crown and anti-reflective sapphire crystal. Lug width 20 mm.

Frequently asked questions

What is the lug width of the Rolex Day-Date 36 ref. 118388-0046?

The lug width (also referred to as anse width) of the Rolex Day-Date 36 118388-0046 is precisely 20.00 millimetres. This measurement defines the distance between the two metal flanges that accommodate the strap lugs. A compatible strap must have a 20 mm lug width to fit correctly without lateral play or mechanical obstruction. Precision is essential: even a 1–2 mm variance would compromise compatibility and function.

Which strap material is most suitable for the Day-Date 36 in yellow gold?

For a Day-Date 36 in yellow gold, vegetable-tanned alligator represents the most aesthetically coherent choice. The medium grain of the reptile and natural tones (dark brown, cognac, black) create elegant contrast with the gold without competing visually. Alternatively, Italian Tuscan calf leather offers superior tactile character with a patina that develops over time. Shell cordovan is ideal for those seeking controlled ageing and natural lustre. Vulcanised rubber, paired with a gold deployante, represents a contemporary option for summer wear.

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

Changing the strap on a Rolex Day-Date 36 requires specific tools: a spring bar removal tool and a protected work surface. Locate the spring bar inside each lug of the case—this small spring retains the strap in position. Use the tool to gently compress the spring, sliding one end of the old strap out of its seat. Repeat on the opposite side. Insert the spring bar of the new 20 mm strap into one lug seat, then push the strap until the spring clicks into the opposite seat. If you lack the necessary experience, consult a qualified watchmaker or specialised atelier such as Casati Milano.

Is an aftermarket 20mm strap compatible with the Rolex Day-Date 36 118388-0046?

Yes, any quality strap with a 20 mm lug width is mechanically compatible with the Day-Date 36 118388-0046. Mechanical compatibility is guaranteed by matching the lug width. However, aesthetic and qualitative compatibility requires conscious selection: the prestige of a Rolex in yellow gold merits a strap in artisanal leather (alligator, calf, shell cordovan) constructed with equivalent rigour. Straps in regenerated or synthetic leather would diminish the watch's value. Engaging specialised artisans ensures both mechanical compatibility and visual harmony.

How long does a leather strap last on a Rolex?

The lifespan of a leather strap depends on leather quality, daily wear and maintenance practices. A premium leather strap (alligator, Italian calf, shell cordovan) of artisanal manufacture typically lasts between 3 and 7 years of regular use. Alligator and shell cordovan demonstrate superior longevity due to fibre density. Primary wear occurs on the loop (the section circling the wrist), where constant pressure and movement deteriorate the material. Casati Milano straps include an 18-month warranty against manufacturing defects. To extend strap lifespan, alternate between multiple straps and protect them from excessive humidity and perspiration.

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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Casati Milano · Via XX Settembre 15, Milan · by appointment only