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The Crystal Luna V02 is a lightweight smart ring that tracks sleep, heart rate, stress, blood oxygen, activity and menstrual cycles, then summarizes it through a built-in AI assistant. Its 2mm profile and 2.5g weight make it easy to wear overnight and during workouts, and IP68 sealing covers sweat, showers and swimming. It competes with rings like Oura and Ultrahuman on the same core metrics, but has a smaller review base and a sizing system of its own, so fit matters more than usual. It suits people who want passive health tracking without a watch on their wrist.
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With 38 ratings averaging 4.7 out of 5, buyers mostly report comfortable all-day wear and useful sleep and activity data. Complaints center on getting the size right and on the ring's own sizing scale.
The Crystal Luna Smart Ring V02 is a smart ring that tracks sleep, heart rate, stress levels, blood oxygen, physical activity and menstrual cycles. It uses multiple sensors to collect this data continuously.
A built-in AI assistant provides a personalized report and guidance on wellness and daily habits.
The ring has a profile 2 mm thin and weighs 2.5 g. It has an IP68 waterproof rating. It is designed to stay out of the way during workouts, running, diving, sleep and work. Its sizing standard differs from standard ring sizes, so check the sizing before you buy.
