Longines UltraChron Ref.8318 Cal.431 35.0mm 1973

Vintage Longines character from 1973. The high-beat Cal.431 brings a lively mechanical rhythm. A non-luminous example with enduring collector appeal.

In addition, this timepiece comes freshly serviced with all parts laid out by our professional watchmaker for all to see in the images above. Little to no other dealers do this and it’s a testament to full transparency here at Montre D’or. With the Cal.431 inside running excellently as shown in the timegrapher reading above, just like it was when it left the factory 53 years ago.

DIAL:

• Original silver sunburst dial in excellent vintage condition
• Baton hands with black inserts and no lume
• Faceted applied hour markers with black inserts and no lume
• Original applied Longines logo with crisp wording
• 3 o’clock date window with perfect balance

CASE:

• Sharp round classic dress case with slim proportions
• 35.0mm Diameter (excluding crown)/ 40.0mm Lug-to-lug / Approximately 10.0mm Thickness
• Approximate reference dimensions; thickness is an estimate from a comparable Ref.8318-3
• Professionally polished with all sharp edges intact
• Original Longines crown at 3 o’clock

CASEBACK:

• Screwdown caseback with UltraChron emblem
• Professionally polished to perfect vintage condition
• Comes with plastic protective sticker as shown

MOVEMENT:

• Longines Cal.431 – Automatic high-beat mechanical movement
• 25 Jewels / Approximately 40.0 Hours Power Reserve / 36,000 BPH
• Date set by turning hands between 9pm to 12am repeatedly
• Movement freshly serviced and in excellent condition

STRAP:

• Handmade leather strap, colour and design can be changed upon request depending on availability
• Aftermarket Longines stainless steel buckle

AFTERCARE PACKAGE:

• Comes with a black presentation box + silica gel
• Complimentary PolyWatch crystal polishing kit (for acrylic crystal)
• 6-month warranty (covers non-user damage only)
• Guarantee Certificate with full service details included
• Access to our exclusive post-warranty repair services
• 7-day return policy for peace of mind

SPECIFICS:

Maker: Longines

Model: Ultra-Chron

Year: 1973

Case Material: Stainless Steel

Reference: 8318

Movement Serial: 51088345

Caliber: 431

Diameter: 35.0mm

Lug to lug: 40.0mm

Lug width: 18.0mm

Thickness: Approximately 10.0mm (reference estimate)

Lume: None

Strap: Handmade leather strap

Box and papers: No original box or papers; Montre D’or presentation box and Guarantee Certificate included

Accuracy: -1s/day

Movement type: Automatic high-beat

Crystal: Acrylic (reference specification)

Crown: Original Longines crown at 3 o’clock

Last service: September 2026

Free express tracked shipping with signature upon delivery. Delivery within Singapore in 1-2 working days. International shipping may take 2–12 working days depending on destination and will be shipped via FedEx/UPS/Aramex/SingPost

Do note respective custom duties might apply which includes the recent US tariffs and are the buyer's responsibility.

Do note that for US and South America bound shipments the PolyWatch polishing kit will not be included in order to mitigate customs delay due to customs requirements

Countries that we do not ship to: Afghanistan, Belarus, the Central African Republic, Chad, Cuba, the Democratic Republic of the Congo, Eritrea, Iran, Iraq, Lebanon, Libya, Israel, North Korea, Oman, Pakistan, Russia, Somalia, South Sudan, Syria, Ukraine and the Crimea, Donetsk, and Luhansk regions of Ukraine.

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.