Longines ULTRA-CHRON CLASSICvsYema Skin Diver Slim CMM.20
The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.
At a glance
23 of 29 specs differFull specifications
Case
9 specsCrystal & Dial
6 specsMovement
7 specsPricing
1 specsFollow this matchup
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Owners + reviewers, side by side
Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.
The Longines ULTRA-CHRON CLASSIC is widely praised for its high-beat 5Hz movement, offering superior accuracy and a smooth seconds hand, with reviewers noting its TIMELAB certification for chronometer standards. Owners and reviewers alike commend its faithful retro design, capturing beloved 1960s details with modern relevance and a charming appearance. The bracelet is described as comfortable and refined, featuring a micro-adjustment clasp, and the sunray silver dial with sparkling indices is a notable strength. Some owners, however, find the 11mm thickness detracts from a vintage feel, and there is a desire for a no-date version. The 40mm case wears larger than expected, with many suggesting the 37mm version offers superior wearability and fit for most wrists, and its 50m water resistance is considered not exceptional. Overall, owners and reviewers rate the Longines ULTRA-CHRON CLASSIC highly for its accurate high-frequency movement and successful retro design at its price point.
The watch's high-beat movement, certified by TimeLab Geneva as an Ultra-Chronometer, is a notable feature. The relatively high price compared to its competitors is a drawback. Reviewers disagree on the optimal case size, with one reviewer mentioning 41mm and 43mm, and the other mentioning 37mm and 40mm.
Owners and reviewers widely praise the Yema Skin Diver Slim CMM.20 for its balanced 39mm case, vintage aesthetic, and unique champagne dial. The proprietary CMM.20 micro-rotor movement is a notable feature, though some owners report potential QC issues including erratic timegrapher readings and second-hand stutter. The lume is described as subdued, and while some find the "dragon scale" bracelet beautiful, others consider it generic. The price point is a hurdle for some, and the stamped clasp quality is considered subpar by one reviewer, with a gap noted by an owner. The lack of hacking seconds is flagged as a drawback at its price. Overall, owners and reviewers rate the Yema Skin Diver Slim CMM.20 highly for its vintage charm and balanced wearability.
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