Rolex · Day-Date 36

Strap for Rolex Day-Date 36 1836

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
Reference1836
FamilyDay-Date 36
MovementAutomatic
Year1960s-70s
CaseGold
CrystalPlexyglass
Water resistance50

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Straps for the Day-Date 36 1836

Selected for the 20 mm lug width · workshop selection

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The Day-Date 36 1836, seen from the bench

The Rolex Day-Date 36 reference 1836 is a significant complete calendar watch from Rolex production in the 1960s–1970s. Originally launched in 1956, it features simultaneous day and date display in 18-karat yellow gold, distinguishing it from the Datejust family. The 36 mm round case houses either the automatic caliber 1555 or 1556, both with 19,800 vph balance and approximately 48-hour power reserve. The case includes a screw-down case back, Twinlock crown, and 50-meter water resistance. Lug width measures 20 mm, compatible with standard aftermarket straps.

Frequently asked questions

What is the lug width of the Rolex Day-Date 36 reference 1836?

The Rolex Day-Date 36 reference 1836 has a lug width of 20 mm, measured between the lower lugs of the case. This dimension is consistent across the entire Day-Date 36 range, regardless of case material or dial variant. The taper towards the buckle is typically 16 mm.

What is the best strap for the Rolex Day-Date 36 1836?

For the Day-Date 36 ref. 1836 in 18k yellow gold, an alligator strap in burgundy, cognac or midnight blue is the most coherent choice with the watch's formal character. Vegetable-tanned calf leather is an alternative that develops patina over time, while shell cordovan offers a compact grain and a luxurious appearance with a strong artisanal quality.

How do you change the strap on a Rolex Day-Date 36 1836?

The strap on the Rolex Day-Date 36 ref. 1836 is secured to the lugs via 20 mm spring bars. To remove it, use a spring bar tool or a fine-tipped pry tool to compress the spring bars and slide the strap free. Care must be taken not to scratch the gold lugs during the process. It is advisable to entrust the operation to a watchmaker or specialist atelier.

Are there aftermarket straps compatible with the Rolex Day-Date 36 1836?

Yes, the Rolex Day-Date 36 1836 accepts any aftermarket strap with a 20 mm lug width and a standard 16 mm taper. Milano Straps produces handcrafted compatible straps in alligator, calf leather, shell cordovan and other selected materials, with buckles in steel or gold-tone metal. Compatibility is ensured by the standard spring bar sizing.

How long does a leather strap last on a Rolex Day-Date 36 1836?

The lifespan of a leather strap depends on the material, care and daily use. A high-quality alligator strap, rotated with at least one other strap and kept away from water and excessive perspiration, can last between three and five years while retaining good structural integrity. Vegetable-tanned calf tends to last slightly less but develops a patina valued by collectors. Casati Milano straps carry an 18-month warranty against manufacturing defects.

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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