IWC Calatrava R820AD C.8541 "Jumbo" 36.5mm 1969

A beautifully example of the IWC Calatrava Ref. R820AD, affectionately known as a “Jumbo” for its generously sized 36.5mm case—an uncommon diameter for late-1960s dress watches. Produced in 1969, this understated piece captures the elegance of Swiss watchmaking from the golden era. It features a crisp silver sunburst dial, a screw-down caseback, and the iconic fish-logo crown. Professionally polished to near mint condition, it's a highly collectible piece you will rarely see on the market today.

Housed within is IWC’s highly regarded in-house automatic movement, the Caliber 8541B, equipped with the Pellaton winding system and whats known to be IWC's epitome of mechanical movements right before the Quartz crisis. Freshly serviced and keeping excellent time, this is a clean, refined vintage dress watch ready for daily wear or special occasions.

DIAL:

• Original silver sunburst dial in outstanding condition

• Applied IWC logo and printed "International Watch Co. Schaffhausen" script

• Sharp dauphine hands and faceted baton hour markers with crayon-like texture

• Applied minute marker dots circling the dial's periphery

CASE:

• 36.5mm stainless steel case (without crown)

• 45.0mm lug-to-lug / 19.0mm lug width / 11.5mm thickness

• 3-body construction with screw-down caseback

• Professionally polished with sharp faceted lugs preserved

• Rare case iteration with brushed sides and mirror polished front (More common would be fully mirror polished)

• Original IWC-signed fish logo crown at 3 o'clock

CASEBACK:

• Screw-down stainless steel caseback

• Clean surface with minimal tool marks

• Reference and case serial engraved internally

MOVEMENT:

• IWC Caliber 8541B – Automatic with Pellaton winding

• Date set by moving minute hand between 9pm and 12am repeatedly

• 19,800 vph / 40-hour power reserve / 23 jewels

• Movement serial: 

• Last Service: May 2025

• Accuracy: ~0s/day

STRAP & BUCKLE:

• Aftermarket black ostrich leg leather strap (19mm lug width)

• Aftermarket IWC-signed stainless steel buckle

AFTERCARE PACKAGE:

• Comes with a black wooden box + silica gel

• Complimentary PolyWatch crystal polishing kit (for acrylic crystal)

• 1-month warranty (covers non-user damage only)

• Warranty card with full service details included

• Access to our exclusive post-warranty repair services

• 7-day return policy for peace of mind

SPECIFICS

Maker: IWC

Model: Calatrava

Year: 1969

Case Material: Stainless Steel

Reference: R820AD

Case Serial Number: 1916539

Movement Serial Number: 1944879

Caliber: IWC Cal.8541B

Power Reserve: 40 hours

Accuracy: ~0s/day

Diameter: 36.5mm

Lug to Lug: 45.0mm

Lug Width: 19.0mm

Thickness: 11.5mm

Lume: NIL

Strap: Aftermarket black ostrich leg leather strap

Buckle: Aftermarket IWC signed buckle

Box and Papers: NIL

Movement Type: Automatic

Crystal: Original IWC domed acrylic

Crown: Original IWC-signed fish logo crown

Last Service: May 2025

Free tracked shipping via SingPost. Delivery within Singapore in 2–3 working days. International shipping may take 4–16 working days depending on destination.

This is a vintage timepiece and water resistance is not guaranteed. Please avoid contact with water or moisture. Store the watch with dry tissue or silica gel to preserve its condition. We are not liable for water damage post-purchase.