Longines Ultrachron Ref.8317 Cal.6651 36.0mm 1974

Available now would be a beautiful Longines UltraChron Ref.6317 in a stunning C-shape case configuration. Powering this watch is the impressive Longines Caliber.6651 automatic movement, one of the brand’s most respected calibers of the period. Known for its reliability and smooth sweeping seconds hand, the Ultrachron movements represented Longines’ dedication to accuracy during a highly competitive era in Swiss watchmaking. The watch is fitted on a striking stainless steel milanese mesh bracelet that perfectly complements the case and gives it a distinctive 1970s aesthetic. Stylish, historically significant, and technically impressive, this Longines Ultrachron 8317 is a fantastic addition for collectors seeking a unique vintage timepiece.

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.6651 inside running excellently as shown in the timegrapher reading above, just like it was when it left the factory nearly half a century ago.

DIAL:

• Original silver sunburst crosshair dial in excellent vintage condition

• Baton steel hands with black inserts

• Applied hour indices with matching black inserts

• Original Longines logo with crisp original wording

• Domed acrylic crystal

CASE:

• Distinctive C-Shape Ultrachron case design

• 36.0mm Diameter (excluding crown)/ 40.5mm Lug-to-lug / 11.0mm Thickness

• Professionally polished with all sharp edges intact

• Original Longines-signed crown at 3 o’clock

CASEBACK:

• Screwdown steel caseback with original hallmarks

• Professionally polished to perfect vintage condition

• Comes with plastic protective sticker as shown

MOVEMENT:

• Longines Cal.6651 – Automatic high-beat movement

• 17 Jewels / ~42 Hour Power Reserve / 36,000 A/h

• Semi-quickset date function (adjusted by advancing hands past midnight repeatedly)

• Movement freshly serviced and in excellent condition

• Last serviced: March 2026

• Accuracy: +2.0s/day

BRACELET:

• Handmade Longines-style stainless steel milanese mesh bracelet, fits almost any wrist size

• 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: Ultrachron

Year: 1974

Case Material: Stainless Steel

Reference: 8317

Movement Serial: 52054501

Caliber: Longines Cal.6651

Diameter: 36.0mm

Lug to lug: 40.5mm

Lug width: 18.0mm

Thickness: 11.0mm

Lume: NIL

Bracelet: Longines Stainless steel milanese mesh bracelet

Box and papers: Box only

Accuracy: +2.0s/day

Movement type: Automatic

Crystal: Domed acrylic

Crown: Original Longines-signed crown

Last service: March 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 bound shipments the PolyWatch polishing kit will not be included in order to mitigate customs delay due to new 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, 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.