9121_A

PATEK PHILIPPE WHITE GOLD AND ONYX REF. 3729G

Patek Philippe 18k white gold octagonal wristwatch with Onyx dial, made circa 1978

Specifications Story behind the watch Collectability says
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Watch Specifications

Reference Number
3732G
Production Year
Circa 1978
Original Date of Sale
Circa 1978
Size
34 mm x 28 mm
Material
18K white gold
Dial Color
Onyx
Watch Movement
Manual Caliber 215
CSKU
9121

Collectability says

The ref. 3729G is the kind of Patek Philippe that rewards a more considered eye. Understated, elegant, and quietly uncommon, it reflects a side of the manufacture that is less about instant recognition and more about its design and quality.

9121

Story behind the watch

Produced from 1976-1990, this unusual watch features the workhorse caliber 215 and a case by Atelier Rèunis. Elegant with a bold design, it appeals to collectors who appreciate proportion, subtlety, and the less-traveled corners of Patek Philippe history. For us, watches like this are especially compelling because they invite closer study of the design and remind us that some of the most rewarding Patek Philippe references are not always the most immediately recognizable.

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Every timepiece is authenticated and backed by our in-house expertise.

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Worldwide delivery

Insured global shipping ensures each watch arrives ready to wear.

How it works

Our team of watch experts is dedicated to ensuring you receive the best possible service buying your luxury timepiece.

1

Find a Patek Philippe you like

Explore the available Patek Philippe watches on the website.

2

Know the watch

Learn about the history, craftsmanship, and value of the watch.

3

Make the purchase

Once you've decided, complete the secure purchase.

4

Receive the watch

You will receive your watch securely packaged in our box, complete with its accompaniments.

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Led by Patek Philippe expert John Reardon, we guide collectors in making confident vintage watch decisions.

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We offer properly vetted, historically significant watches for serious collectors.

Buy a watch

Every timepiece is personally inspected and authenticated by our founder, John Reardon, one of the world’s leading experts on Patek Philippe. The case, dial, movement, and, when applicable, the buckle and bracelet are examined before a watch is offered for sale. Whenever possible, we include the original Certificate of Origin or an Extract from the Archives. If a watch is offered without one, we will always explain why - for example, if Patek Philippe declined to issue an Extract from the Archives because a dial was changed at some point in the watch's history.

We take pride in offering watches in the condition in which we acquired them. We avoid unnecessary interventions such as polishing or dial refinishing. If a movement requires repair, it is serviced by our select group of trusted specialists, including Patek Philippe-trained watchmakers.

Yes. We guarantee the authenticity of every Patek Philippe timepiece we sell. If a watch purchased from us is ever determined to have a previously unknown issue, please contact us to discuss the issue. This authenticity guarantee lasts two years from the date of sale and applies only to the original purchaser. It covers the watch as a whole, not individual components. All trademarks mentioned are the property of their respective owners. Collectability is an independent business and is not an authorized Patek Philippe dealer nor affiliated with Patek Philippe SA.

Every watch purchased from Collectability is guaranteed to be in working order for one year from the date of sale. If it stops functioning properly during that period (and hasn’t been damaged or mishandled), we’ll repair or adjust it free of charge.

Vintage and pre-owned watches should never be considered water resistant, even if they were originally designed as such. We recommend avoiding exposure to water, shocks, or magnetic fields.

For most timepieces, with the exception of consigned pieces, if you decide your timepiece is not right for you, you can return it within three business days for a full refund provided that the timepiece and its accompaniments are in the exact condition they were shipped to you. We’ll issue your refund upon safe receipt of the watch and any or all accompaniments.

We accept secure payments via bank transfer only.

Yes. All shipments are insured until they reach you via a trusted courier.

Returns are accepted within three business days of delivery for a full refund. We’ll provide a prepaid label and issue the refund upon safe receipt of the watch.

We’ll arrange immediate repair or adjustment under the terms of our one-year working guarantee.

Within the first year, repairs within reason are covered. After this period, we can coordinate servicing with our watchmaking partners at your expense, with an estimate provided before any work begins.

Yes. Many clients choose to have us coordinate ongoing maintenance or service.

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Testimonials

Tom P ○

“Just received a watch this morning purchased through Collectability. From start to finish it was a pleasurable experience and went very smoothly. Collectability definitely has the most interesting and quality curated inventory of vintage Patek Philippe I have seen. 10/10 would recommend.”

JH ○

September 2025

“Downsizing my life in many ways big and small. Checked several sources looking for a reputable buyer of Patek Philippe. John’s name came to the top of the list as an expert. I reached out to him and he offered a very fair price (I had gone to other dealers and researched online)He offered several w…”

Doc ○

July 2025

“I’ve had the pleasure of purchasing two vintage Patek Philippe watches from Collectibility, and I couldn’t be more satisfied with the entire experience. From the initial inquiry to post-purchase support, the service provided has been nothing short of exceptional. John Reardon is a true authority wh…”

Marc ○

June 2025

“I bought a watch and John and Tania could not have been better to deal with.”

Gerhard Z ○

June 2025

“John is THE authority on everything Patek Philippe! He is not only trustworthy, but also a genuine pleasure to talk with!”

Peter S ○

May 2025

“I am a New York City physician and distinctly honored to have recently purchased several exquisite, rare, pristine and well-priced Patek Philippe timepieces and accessories from John Reardon, founder of Collectability. John is the real deal you can't find anywhere else when it comes to being knowle…”

David T ○

April 2025

“I just opened the box with the Patek Philippe watch and paperwork from Collectability. Not only is the watch stunning, but the quality of the packaging and the overall presentation was the best I have ever seen. I am extremely impressed. You really made the buying experience absolutely first class.…”

Robert M ○

March 2025

“John was very patient. I thought I knew a lot about Patek Philippe since I worked in an authorized dealership many years ago. I was wrong. As a lifelong Patek fan, I really appreciate the patience and assistance. My watch is amazing. Every aspect of my purchase exceeded expectations. Thank you!”

BLN ○

February 2025

“Collectability’s integrity, knowledge and service elevate an enjoyable hobby to a passionate quest for scholarship and collection. I have dealt with the team at multiple occasions over the years, and what I found truly remarkable is the combination of generosity in sharing knowledge and unmatched e…”

Andres N ○

January 2025

“You [John Reardon] and your team are really amazing and some of us are very fortunate that we not only have been able to get some amazing Patek Philippe pieces through you, but we have learned a lot as part of the process.”

Marc B ○

December 2024

“Over the past 4 years, I have bought and sold over a dozen Patek Philippe timepieces with Collectability. John Reardon and Tania Edwards are not only world-class experts when it comes to Patek Philippe, they are also world-class individuals. They set the bar high for everything from the educational…”