Rolex
Day-Date 36 118238-0110— lug 20mm

The lug width of the Rolex Day-Date 36 reference 118238-0110 is 20 millimetres. This measurement is specific to the 36-millimetre Day-Date models and represents the distance between the case lugs where the strap is attached. A 20mm strap fits precisely without any play or movement within the lugs.

For the Day-Date 36 in yellow gold, the optimal pairing is dark brown or cognac alligator: the glossy texture of crocodile leather reflects light like gold, creating visual continuity. Alternatively, vegetable-tanned calf leather develops noble patina over time, whilst shell cordovan in burgundy offers aesthetic depth during evening hours. Vulcanised rubber remains ideal for those who wear the watch in aquatic environments.

The Day-Date 36 strap is replaced by unscrewing the lugs (spring bars) from the case using a dedicated spring bar tool. Insert the tool tip into the lug hole, press downwards to compress the internal spring, then extract the bar and old strap. Insert the new 20mm strap into the lugs and reinstall the spring bars. Verify that the strap is securely anchored before wearing the watch.

A quality aftermarket strap for the Day-Date 36 must feature a 20-millimetre lug width and noble materials: alligator, vegetable-tanned calf, or shell cordovan. Selection depends on desired aesthetic — formal with dark brown alligator, versatile with cognac calf, elegant with burgundy shell cordovan. Casati Milano offers bespoke artisanal straps with an 18-month manufacturing guarantee, crafted in their Milan atelier with personalised leather selection.

A quality leather strap on the Day-Date 36 lasts between 4 and 8 years depending on material and daily wear. Alligator resists longer owing to leather density; vegetable-tanned calf improves over time but develops visible patina after 3–4 years; shell cordovan achieves 7–10 years of serviceability. Direct sunlight exposure, humidity, and perspiration shorten durability. Regular maintenance — gentle cleaning with a damp cloth and light conditioning — significantly extends the strap's lifespan.