With the new Ultra-Chron Carbon, Longines continues bolstering its already impressive lineup. Plus, the watch features the brand’s first-ever carbon fiber case. This is a beautiful dive watch with an outstanding movement.Longines reintroduced the stainless steel Ultra-Chron in 2022, and it was praised for its 36,000vph movement and design, which evokes the 1968 original. Now there’s a new variant. The Ultra-Chron Carbon follows a similar form but looks strikingly different.The Longines Ultra-Chron CarbonThis watch uses the brand’s first carbon fiber case and pairs it with a titanium crown, bezel, and case back. Due to this, the 43mm by 48mm diver weighs just 80 grams. A domed sapphire crystal brings the thickness to 13.6mm, which is reasonable for a watch with a 300m water resistance rating. The screw-down crown and screw-in case back reinforce this capability. Unlike the steel version with a bracelet, this watch is available exclusively on a black technical fabric strap with a titanium buckle. A successful mix of black and grayThe Ultra-Chron Carbon blends a layered carbon fiber case with titanium details, including a 60-minute bezel with a black aluminum insert. The sand-blasted anthracite dial contains applied and polished metal indices. Longines chose titanium-matching gray PVD-coated hands and uses blue-emitting Super-LumiNova throughout the dial. Thankfully, the absence of a date window continues, which leaves a perfectly symmetrical dial.A chronometer-certified high-beat movementThe Ultra-Chron Carbon uses the Longines L.836.6 automatic caliber with a silicon hairspring. It features 52 hours of power reserve and has a high-speed 36,000vph frequency. Notably, it also carries a chronometer certification from the Geneva, Switzerland-based firm Timelab. At the laboratory, each movement undergoes 15 days of testing in various positions and temperatures to certify an accuracy tolerance of one minute per month.ConclusionsThe Ultra-Chron Carbon is available now for US$4,900 online and at authorized Longines retailers. That’s not inexpensive, but this competes with watches like the Tudor Black Bay Ceramic and the Doxa Sub 300 Carbon. Design-wise, it’s hard to deny the model’s attractiveness, and the movement is a genuine adder. Some will mention concerns over the size, but the relatively short lug-to-lug allows it to wear well on various wrists. We look forward to providing a hands-on review, but for now, let us know what you think about the brand’s latest diver! Watch specifications Brand Longines Model Ultra-Chron Carbon Reference L2.839.4.52.2 Dial Sand-blasted anthracite gray with applied silver luminous indices and gray PVD-coated hands Case Material Carbon fiber with titanium crown and bezel and aluminum bezel insert Case Dimensions 43mm (diameter) 48mm (lug-to-lug) 13.6mm (thickness) Crystal Sapphire with multilayer antireflective treatment Case Back Titanium, screw-in Movement Longines L.836.6: automatic with manual winding and hacking, 36,000vph frequency, 52-hour power reserve, 25 jewels, silicon balance spring, chronometer-certified Water Resistance 300 meters (30 bars) Strap Black technical fabric with titanium buckle Functions Time (hours, minutes, seconds), 60-minute diver's bezel Price US$4,900 Warranty Five years