Rolex · Day-Date 36

Strap for Day-Date 36 Yellow Gold Diamonds / Oyster / Silver 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
Reference118388-0185
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 118388-0185

Selected for the 20 mm lug width · workshop selection

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The Day-Date 36 118388-0185, seen from the bench

The Rolex Day-Date 36 118388-0185 in yellow gold represents contemporary presidential watchmaking. Launched in 1956 as the first wristwatch with dual calendar windows (day and date), it maintains classic proportions with a 36mm case. The watch houses the automatic caliber 3155, developed internally by Rolex, certified to ±2 seconds per day. The strap width is 20mm.

Frequently asked questions

What is the lug width of the Rolex Day-Date 36 118388-0185?

The Rolex Day-Date 36 118388-0185 features a lug width of 20 millimetres. This measurement is the internal spacing between the attachment points of the spring bar housing. You can verify this dimension using a digital calliper positioned at the lateral holes of the case, or by consulting your Rolex certificate of authenticity. Incorrect measurement risks purchasing an incompatible strap.

What is the best strap material for a Rolex Day-Date 36 in yellow gold?

For a Day-Date 36 118388-0185 in yellow gold, alligator remains the most sophisticated choice: the flat-scaled texture does not compete with the brightness of the gold and maintains understated elegance. Vegetable-tanned calf offers a patina that evolves naturally over time, increasing character. Hungarian shell cordovan guarantees natural rigidity and density that enhances wrist presence. For modern versatility, FKM rubber in black or dark blue creates bold contrast whilst preserving elegance.

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

Changing the strap on a Day-Date 36 requires a specific tool: a spring bar tool (Y-shaped screwdriver or spring bar removal pin). Position the sharp edge beneath the visible spring mechanism at the case lugs, then press downward to disengage the housing. Once the first side is released, gently extract the metal bar and proceed with the opposite side. Reinstalling the new strap follows the reverse procedure. If unfamiliar with the process, a certified watchmaker can complete the operation within minutes.

Which aftermarket straps are compatible with the 118388-0185?

Any strap featuring a 20-millimetre lug width is compatible with the Day-Date 36 118388-0185. This encompasses alligator, calf, crocodile, FKM rubber and technical fabrics provided they mount a standard universal spring bar. MilanoStraps offers a comprehensive collection of artisanal 20mm straps, many crafted bespoke at the Casati Milano atelier. Always verify the lug width before purchase to ensure compatibility.

How long does a leather strap last on a Rolex Day-Date 36?

The lifespan of a leather strap depends on material quality and usage conditions. High-quality alligator maintains functionality and aesthetic appeal for 5-7 years with regular maintenance. Vegetable-tanned calf requires more frequent conditioning (every 3-6 months) and typically lasts 3-5 years before replacement becomes necessary. Shell cordovan, owing to its natural density, can last 8-10 years. FKM rubber typically lasts 4-6 years. The decisive factor remains frequency of exposure to moisture, perspiration and direct sunlight.

The next step

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